What do I do if my players are acting in a way that is meta-gaming and are refusing to accept my decision?

Question

The Situation

I have a party of 5 players all sleeping in a barn on an abandoned farm at night. This is near the beginning of the campaign and each player likes having little secrets about each other.

Two of my players, let's call them John and Jim, want to talk to each other because their characters formed an in-game friendship, so they sneak out of the barn and go behind the building to talk to each other.

Afterwards, one of the other players, let's call him Frank, has an in-character nightmare issue. He has to roll a check in order to sleep. After John and Jim left to talk, Frank woke up from a nightmare. Frank wants to know if he can hear John and Jim talking to each other. I ask John and Jim how loud they are being? Are they whispering? They said "kind of." I take that as there is a chance for Frank to hear them. I have Frank roll for perception with disadvantage and he rolls an 18 and a 19. So Frank can hear John and Jim whispering to each other.

The problem

Frank wants to eavesdrop.

John suddenly tells me that they are speaking in orcish to each other. While both John and Jim can speak Orcish, they never said they would talk in Orcish. I even make sure with every action that they do if they want to do anything else. I ask, "is that all?" Every time. They did not tell me they were going to speak in Orcish until the prospect of someone eavesdropping on them came up.

I think I'm generally fair with things but this felt like a very retroactive declaration. John decides that his character isn't going to talk to Jim anymore, or that he wasn't going to say anything. I told John that's meta-gaming and he says he didn't care and that he should be speaking Orcish. He doesn't want to give away a character secret to Frank.

Impact on play

The session ended sourly and we took a break for the day since he didn't want to accept the ruling but he is willfully breaking character.

Am I being unreasonable as a DM?

I'm thinking of just saying fine and letting them speak in Orcish and moving on but that feels unfair for everyone else. Problem is, this player wants to hide everything about his character from everyone so he never says outright what's going on to me.

It's unfortunate because I've worked really hard making exceptions to everyone's classes in order for everyone to have fun. John's character wants spells like fireball to be lightning instead, so I made every spell have an lightning, thunder or force version of it for him.
For Frank: I made a whole herbal medicine system for him.
I don't want something so small to ruin the vibe of the campaign but it feel important to enforce rulings like this as well.

Answer 1

There are a ton of “same-page” issues here

You are running into these problems because you aren’t all on the same page about what kind of game you’re even playing. It turns out that “Dungeons & Dragons” can be played quite a few different ways, and it’s not necessarily obvious how things work just because you say “Dungeons & Dragons” is the name of the game.

It seems to me that the two players whose characters are getting together for private discussions might be on the same page, but you don’t seem to be with them, and the player whose character had the nightmare doesn’t seem to be with them either—and maybe also not with you.

None of you is wrong, except insofar as you each assume the others are. This is purely a matter of preference. You’ve just missed the step where you discuss what those preferences are, and simply assumed that you could each play your preferred way even though those ways don’t match, are clashing, and may be incompatible.

So your first step is for everyone to discuss how they each want things to go, out-of-character. This is necessarily a “metagame” discussion and that’s OK. Everyone has metagame considerations, and it’s not wrong to have them and want certain things on a meta level. We are all playing to have fun, but what “having fun” looks like varies—so how you want to “have fun” is a metagame concern that you should be thinking about and talking about.

This also means that whether or not these players were “metagaming” is close to irrelevant. It’s not quite—more on that in a bit—but fundamentally you hadn’t reached a point where that player was clearly acting outside the pre-established boundaries for appropriate play: you hadn’t established any such boundaries.

Off the top of my head, some topics your group needs to cover:

• What exactly constitutes metagaming? When is it a problem? When is it a good thing?
  • It is a good thing, at least some of the time. This is important.
• How does each player want to handle their character’s internal arc? Where does a player’s right to control their character end, and where does the DM’s right to control the world start?
  • As DM, you should be extremely leery of suggesting anything is “out of character” for another player’s character.
• How does your group want to handle player-vs-player conflict?

All of these—and probably more—need to be discussed. Also, in these discussions, your role as DM is not especially important. These things can’t be dictated. This is the negotiation where you figure out if, and what, you are playing together. No one is required to play a game they don’t want to play. That includes you—you don’t have to DM anything you don’t want to DM—so that gives you somewhat more leverage (a DM is harder to replace than a player), but at the end of the day, you also need players, and everything here has to be voluntary. This is a game; we do it for fun.

A quick thought: was this metagaming?

One thing I do want you to consider on the subject of whether or not the characters were speaking Orcish is, could this be an issue of reverse metagaming? That is, RPG players are quick to condemn “metagaming,” in the sense of abusing player knowledge the characters would not have, but often overlook the opposite, where players don’t know things the characters definitely do, or fail to consider things that would absolutely occur to the characters. For example, the question of what to bring on a long and perilous journey into the unknown: I, personally, would not even know where to start. My 15th-level ranger and expert explorer probably does—a lot better than I do. So is it “metagaming” to just say he has the supplies that turn out to be necessary, even if I didn’t think of it? A lot of people would say “yes,” but I would probably say “no”—and I think that, either way you come down, it’s a question that deserves more consideration than it often gets.

Likewise, would people having a private conversation in a not-so-private place where they are concerned about being overheard be speaking in a language they each know, but which is not known to many others? Quite plausibly! And if they’re both orcs with Orcish as their native tongue, having an intimate conversation, well, you would expect them to.

These thoughts might start your discussion of what exactly metagaming is for your table.

Deciding to React Differently

One of the most frequently-discussed problems in role-playing is My Guy Syndrome. One of the best resources (after our own excellent answer, which also links to this one) on the subject is Rich Burlew’s Making the Tough Decisions. It sounds like everyone—including you—is guilty of a little of this, so I suggest this is mandatory reading for everyone before having your discussion.

The key here is that to avoid My Guy Syndrome, you have to embrace a certain amount of good metagaming. As Rich puts it, you have to “decide to react differently,” that is, take at least one paramount metagame consideration—how much fun the group is going to have—into account when making decisions. Is it fun for the group if these two get to keep secrets? Is it fun for the group to have those secrets out in the open? I don’t know the answers to those questions, but I do know the dice can’t tell you. This is what you need to discuss.

Many groups simply avoid “PvP” rolls altogether

Obviously, when one thinks “player-vs-player,” one imagines combat. But eavesdropping, lying, sneaking, etc., are all “versus” (read: against) one another. And a lot of groups just don’t do that—that kind of thing is handled by group consensus, what would make for the best story, rather than what the dice say. There may be allusion to relevant bonuses (“my character is really good at lying,” etc.), or an agreement to let the dice decide things, but the base rule is that the group decides. Often with the DM staying out of it. I’ve even argued that when the situation is seduction, dice should never decide matters.

The reasons for this are myriad, and you’re running into many of them yourself: having your characters’ own internal story as a party decided by dice can lead to bad feelings and strong incentives to behave “poorly.” In effect, a lot of groups think that players should have veto power over another PC influencing their own like this.

So you need to discuss if you are one of those groups. And if you are not, how you want to handle things instead. Or if you even are a group—if the two with the private conversation will only have fun if they get to keep it secret, and the rest of you only have fun if there’s at least a chance of it getting out, then maybe you don’t actually have a game at all. But if you don’t, better to find out now, before things get too bitter. They’re already trending in a bad direction—and if you discuss it, and find out there just is no answer that keeps everyone happy, at least you can avoid the fallout. And you might just find out that there actually is a compromise that makes everyone happy, and then you’ll be able to continue on. But only if you discuss and find out what it is.

Answer 2

Frame Challenge: Secrets are usually boring or game breaking

Having played RPGs for decades I can say with confidence having in-game secrets mostly leads to two situations: a) boring - the secret's reveal is anticlimactic or worse never gets revealed or interacted with at all or b) leads to intra party conflict (often out of character). Occasionally you can get a great reveal that'll make everyone's jaw drop but that is such a rarity that it's really not worth the effort. There are some other RPGs that do handle secrets better than D&D, but then the mechanics are usually built into the game.

If you trust your players and can get them to trust each other secrets can still be interesting if they're only secret In Character. Then, the Player's whose characters don't know can still help the plot come to an interesting conclusion. In your example, I'd have the eavesdropper hear them whispering in Orcish but not being able to understand they'd either have to go back to sleep or interrupt. Assuming they didn't interrupt I'd then have Jim & John have their secret conversation out loud. In Character Frank and the rest of the party don't know what was said, but the PLAYERS do know (and implicitly are promising to only act on this information in ways that would make things more fun for everyone)...

Being able to keep IC and OOC knowledge separate is a great skill for making games more interesting, and many RPG Horror stories are based on people not being able to keep that separate and especially abusing this knowledge to try and "win" the game - except of course RPGs don't have a "win" state - you win by having fun with your friends. It may be that your group doesn't have the maturity to do this, but the best way to find out is to talk about it (out of character of course) and then try. If you can get everyone on the same page, you'll find you have richer stories and more fun in the long run. Plus imagine if Frank (but not Frank's character) knows the secret and keep's having his character "just missing" stumbling upon it. It could easily become a hilarious running gag and a lot of fun narratively trying to figure out how he fails yet again to discover the secret long after the rest of the party knows.

Answer 3

Removal of players' agency.

While there's something to what others say about same-paging, this seems like a more serious series of GM failures, most of which are pretty much never OK regardless of same-page agreements.

Ignored player intent

The players explicitly stated they were stepping outside to discuss something privately. The GM had no apparent confusion about this: he understood that the clear intent of the players was to move their PCs to where they could safely have a private discussion.

The GM subverted the player's agency to do so, by allowing a roll to make their location choice invalid to their privacy, and to have their whispers audible through a solid wall. He didn't even give them any kind of saving throw or ability to detect or act upon the eavesdropping, nor a stealth check to succeed at being stealthy.

"Is that all?"

This question doesn't absolve a GM from giving players the info they need to make their decisions.

Asking "is that all" when players have their PCs move outside to speak privately where the other PCs can't hear them, then only afterwards rolling to see if they're somehow still within whisper-hearing-range of another PC, is like asking "is that all?" after they declare their actions to sneak up and silently take out a goblin, and only then rolling to see if the goblin's riding a Dragon.

I'd go so far as to say: never ask this, if what you mean is "There's something you missed, can you guess what it is?". Because the challenge of the game shouldn't ever be "can we second-guess the GM?" Screwing the PCs is not the job of the GM.

"are you sure you want to...?"

Whenever they might not have deliberately chosen to use their agency to attempt the risky and/or dumb thing they just said they were, you can and should use this question.

"Are you sure you want to step out of the shadows and offer a sandwich to the necromancer, surrounded by three dozen armed skeletons, literally crackling with magical energy... while you're wet and naked?" "Yes, I'm sure." "Oookay. Charisma roll. Disadvantage..."

In this case, the unasked question was "Are you sure you want to stand by the toiletpaper-thin wall, as you have this discussion in Common?".

Or don't even ask: assume common sense

Sometimes, clarifying questions aren't worth asking. For example, the GM here wisely didn't ask "are you moving somewhere that there's no chance of being overheard and still talking in Orcish, or standing somewhere that even a sorta whisper has a 1-in-8 chance of being overheard and talking in common?" ... because, if he had, he knows what they'd have answered. They already stated their intent: to speak privately, not "sorta privately, assuming everyone stays fast asleep", because in that case they would have just stayed in the room with all the sleeping people.

Assume that PCs trying to avoid being overheard, won't talk loudly enough to be overheard.

Assume that in any conversation between two people who share a common language, they will use the least-common language shared by all present.

Assume that people take a long rest have a rotated watch.

Assume that people going on a long trip will know whether they need to buy rations.

Assume that you aren't playing a game of "gotcha" against your players. Screwing the players or PCs is not the job of the GM. Screwing the PCs is the job of the NPCs and situations they encounter.

Good rolls don't grant superpowers

The urge to "reward" good rolls is strong. And if someone gets a good roll with disadvantage, it feels like they got an even better roll, so need an even better reward than if they had got the same result without disadvantage. Treating an 18 and a 19 as if it were higher than both.

But statistically, there's negligible difference between getting an 18 on a D20 (15% odds), and a 6 on a d6 (16.7% odds), so even if you felt the need to reward good rolls... it's not a great roll. And "at disadvantage" should never mean "automatically get a better result if you roll well". Quite the opposite, if anything.

So at those odds, the best the player should have expected was the ability to detect that someone was speaking.

Even a 20 (5% chance) should only give a little extra information: perhaps the muffled speech patterns could let them identify how many people was talking, or who was talking, or what tone their speech was taking.

Hearing precisely WHAT they were saying should not have been possible from that roll in the first place.

PvP, if allowed, should be a two-way street

If the person making the roll then wants to actually eavesdrop well enough to hear words, he needs to take actions, make rolls, etc. He has to do a thing: eavesdrop. That's not a passive action, that's an attack on the agency of the other players. He can't just get it for free.

So, as their eavesdropping action, he might decide to open a window to hear better. Then the speakers will get to notice and respond to it. "A window opens nearby" -> "we switch to Orcish".

Or he could sneak out to listen. In which case they'd have to make a stealth check, and the speakers should get a perception check, but they fail, you're in trouble as a GM.

You can't force players to screw their PCs

By putting the players in the untenable position of "now say the stuff that you don't want to have overheard, for this player to overhear"... you have screwed your players, and yourself.

You're asking them use their imagination to screw themselves. Screwing the PCs is not the job of their players.

HOW DO YOU RECOVER?

Failure shouldn't be a blame game. Everyone will fail. GM slipped up, that's a good thing, means he had a chance to learn things. You don't get experience by succeeding all the time! So how can it be avoided in future? And how can this be fixed once it inevitably happens again?

So, OK: the GM retconned the private talk into a non-private one. Or maybe they failed a perception check to notice someone sneaking up to eavesdrop.

Either way, the GM's got himself into a position where he's violating the rule of not forcing people to screw themselves. Since he can't force someone to screw their own character, it falls to him as a GM to storytell his way out of the corner he's painted everyone into.

This corner-avoidance is a core skill of GMing. Ideally it should be invisible to the players.

For this recipe, you will need one reward, and one ass-pull.

A reward

He should give the eavesdropper something - but that something shouldn't give away the other players' whole farm for the cost of a single passed skill check, nor should it require the players to screw themselves.

The GM can tell the spy that they saw the two characters talking together. The tone of their voices was urgent and conspiratorial. And if he knows what they would have been talking about, he can give additional clues. Perhaps one pointed at the clocktower, and passed some gold; the other checked his crossbow. The spy might incorrectly assume one's paying the other to snipe from the clocktower, rather than saying "be ready for a fight in 45 minutes, go buy some more bolts if you need them" ...and that's OK.

An ass-pull

But after giving that minor reward for showing the initiative to snoop, the GM then has to pull a rabbit out of the hat to save face for the players being snooped on, and avoid them having to actively screw themselves. So roll the dice for color, look on the "town encounters" table, and there's an encounter.

An interruption, a nightwatchman walking down the road. A window flying open and the contents of a bedpan splashing right beside them as a woman screeches "you think I can't hear you whispering outside my room? Whatever you're plotting, do it somewhere else, you 'orrible little thieves!" A footpad attacking the spy for lurking in his territory. A cat chases a rat past them. A snake-oil salesman rolls up in his cart and decides to try to try making one last sale before driving his cart out of the town in the dead of night for no particular reason. A street urchin who's also been spying on them sends a shingle sliding off the roof with a clatter. An ornate cart rides through, clearly in a hurry. It starts to rain. There's a noise from the stables. The innkeeper sticks his head out, making sure they're not running off without closing out their tab...

Literally anything that gives them the narrative excuse to pivot so they're no longer screwing themselves, so that they don't have to come up some silly retcon themselves.

Answer 4

Making decisions for the players isn’t a ruling.

The DM is the final arbiter of the rules. The rules. This is what rulings are - decisions about how the mechanics of the game interact. The DM is not the arbiter of the players’ decisions about what their characters are doing. So when the player “didn't want to accept the ruling”, it is because you weren’t making a ruling, you were taking away the agency and autonomy they had over their character. Agency and autonomy over their characters is pretty much everything the players have here. The DM gets to control everything else in the whole universe, and the player gets to control this one character. Take that away from the player, and what do they have left? The DM should be trying to protect the player’s agency over their character, as it is the whole point of playing this game.

To metagame or not to metagame?

Metagaming can be a controversial issue, as you’ve already seen. Every group I’ve played at has allowed some level of metagaming, since it’s impossible to fully divorce player knowledge from character knowledge. However, every group has been different about how much and what sorts of metagame thinking was okay. Sometimes, it’s easy to feel the vibes and no explicit conversation is necessary. But when there is a conflict, such as your situation, it becomes critically important to set sometime aside as a group to have a conversation about what happened, and how to handle metagaming related issues moving forward.

From what I can tell, you brought to the table an assumption that metagaming was something that as a rule should be avoided, while some of the players involved clearly disagreed, at least in that moment. So you all need to have a conversation and get on the same page about how to handle these sorts of situations. I’m not saying you’re wrong or they’re wrong for feeling one way or another about metagaming, there’s nothing wrong with preferring a particular playstyle. However, as discussed in the first section, I do think your handling of the conflict in the moment was poor. As DMs, we should strive to protect player agency as much as we can, and that was a situation where you could very easily allow them to maintain their agency and then had a conversation after the session.

The key takeaways here are:

1. As a DM, protect player agency as much as you can. Obviously, a player trying to do something outside the boundaries of the rules isn’t player agency. But a character who can speak orcish trying to speak orcish definitely is player agency.

2. Metagaming is a potentially polarizing issue. If you smell conflict around it, get it out in the open and align with everyone else through respectful discussion.

Answer 5

Preface

I believe strongly that there is no right answer to this question. This is going to be something that varies with the unique chemistry of players, GM, and setting from table to table. While there will be strongly held opinions, the point here is to give the querant some (hopefully experience-based) approaches that have been useful in the past.

Is This Metagaming?

The only people who really know are the players of your two orcish-speaking characters. Did they both imagine themselves speaking orcish from the beginning? Did they quickly and quietly retcon to nullify the (frankly amazing) roll with disadvantage that the other player made? Only they really know.

But you, as the GM, who watched the whole scene unfold at the table, and observed body language, facial expression, and tone of voice, are entitled to a firm and actionable opinion, in my view.

Whose Responsibility Is This?

I lean toward making the initial declaration of language the responsibility of the players. And I base this on my own experience in a (non-D&D) game where I run a character who occasionally does use this technique.

I don't think I've ever used it to screen information from fellow PCs, but I've used it to keep NPCs in the dark many times. (As far as I know. I fully expect to do this some day and find out later that the NPC spoke my PC's obscure language.)

But because this is a gambit, I consider it my responsibility to make the language issues clear, rather than springing it mid-scene and confusing everyone.

Having it be otherwise is in my experience a recipe for chaos, because you end up with different players, including the GM, having very different mental models of what is going on.

Also, having the GM question the players out of the blue, "Hey, uh... what language are you guys speaking?" could itself alert the players to a threat in the area. (I'm not thinking of your other PC, which they know about because they are at the same table. I am thinking of a hypothetical spy they don't know about, listening in.)

Precedents

In an established game, though, an argument based on precedent can cut in the other direction. If it's well established that these two characters are always (or even usually!) talking to each other in orcish, well, that's pretty good evidence that they might be speaking orcish now, and just forgot to say it.

There's a similar argument for peculiarities of the campaign setting, for instance, if there is no default or common language.

But if this game is in its earliest stages, you probably don't have many precedents already set. Indeed, you probably set the precedent with your decision, unless you reel it back in shortly. (It happens-- we have to make snap decisions, and sometimes see later there was a better decision.)

Ways To Handle This

One way is to realize that you are making a precent-setting decision, give yourself a minute to think about it and explain or discuss it with the table, and then make and enforce your decision.

But understand that when you do this, you are almost necessarily influencing your players' actions in the future. If you rule that non-Common conversations have to be flagged from the beginning, I can almost guarantee that you hear "Oh, and we're talking in Orcish" at least once per session.

A second way is to let the dice decide. I've actually done that in the game I referenced (although it uses a different randomizer than dice) when I was asked if my character was doing something or using a specific countermeasure. I know my character well enough to answer retroactively and honestly at least some of the time. Other times... enh. Would he really be that paranoid? He's not Batman, he's not always doing the perfect thing.

It's never a great feeling to have to do that. And I expect it will not be a great thing to have it forced on your players. But it's worth a thought.

Note, you can combine these: Set your precedent, and then allow a one-time roll to compensate for the fact that the precedent is new. (I would suggest something wisdom based.)

How Would I Handle This Specific Scenario?

I wasn't there, but I think your guys are metagaming. When you asked if they were whispering, that was the time to provide additional context. When the other player was about to roll, that's a good time, too. But they didn't, it only came up after that, and really looks like a last ditch effort to retcon. And they (I believe) don't have precedent built up in their favor.

I also tend to offload as much of this to the players as possible. I just don't want to play twenty questions with the players over every action they take, on the off chance something will become relevant. In some cases, I refuse to do so because questions give away information. In other cases, I reserve the right to ask pointed questions.

So my reaction would have been, "No, sorry, if you want to be doing something unusual, or taking countermeasures, you need to tell me before it becomes relevant-- that's why security is hard. Sorry you didn't understand that, but now you do, so let's move on."

If, based on my knowledge of the players, I thought that was too harsh, I would probably allow them a wisdom-based check-- and a relatively difficult one-- to see if they thought of it before hand.

Final Thoughts

There is no magical way to make everyone feel good about this, by the way. Someone is going to be disappointed, although mature and experienced tables will handle it better.

Your real focus should be on the future, trying to make sure these events are rare, and that you have a policy you can be both comfortable and consistent with.

Answer 6

Restatement of Situation.

• John and Jim hold a conversation. They have told the location where they hold it to the GM, and that they talk somewhat silently, when asked how loud they are.
• The GM never clearly or proactively inquired about the language they are speaking.
• The GM has someone roll to listen in.
• John and Jim now, after the roll, note for the first time that they were talking orcish.

Conflict Origin: Breakdown of Communication Protocols!

As a result of the situation, conflict brewed. So, the question is, how to proceed? First of all, we need to find a couple of points of failure. All of them boil down to what I believe stems from mismatching expectations, unclear statements, compounded by the inexperience of the GM, and ultimately bad communication. The communication broke down at three different points, and I can't stress it enough, all parties are to blame for that.

Failure point one: Unclear Statements. Nobody proactively and clearly inquired about or stated a language till it was too late! That is a fault of both sides! John and Jim didn't make it crystal clear in the first place, that they wanted to talk in Orcish. But the GM also did not ask them about it clearly, so there was - as a practical matter - no reason for them to state if they were talking Orcish or Common or Urdu. They both have at least one common language, and unless it matters which they talk, they could talk any of them. The players mentioned it late. Maybe they didn't think it mattered until someone listened in, maybe they wanted to exlude the other player, but determining that requires working communication! As such, this is a case of Instructions unclear, insert Batteries where?. The GM can be considered correct in that You did not state that, so you didn't do it! applies, but according to the statement given, they had mentioned no language, so by what means were they communicating at all if they did not state a language? There is no statement they spoke anything. To a good degree, the GM and the players both messed up. While true that the GM asked "Is that all?", that question is a trick question. It would have been the perfect spot to inquire about the language instead, but the GM chose to use the trap question and thus actively facilitated miscommunication by asking a very open-ended question that kept evreything unclear.

Failure point two: Classic miscommunication of expectations. Is there a silent expectation that people speak common at all times unless they note it? That might not have been communicated! It would massively help to sit down and state such to everyone. Expectations such as "please mention languages other than Common/English/High Gothic/Lingua Franca/... when you use them" need to be stated and known! Without having those expectations known, effective communication is hard. It is on both parties to make sure that everybody knows the expectations they have when engaging in the game.

Failure point three: Is everybody on the Same Page with the campaign?! Is really everybody buying into PVP and secret backstories with their gaming expectations in the same way or do they have different goals? it is on everybody around the table to make sure to clearly communicate what kind of game they want to play and how. There are many reasons why people discuss things in secret or listen in to such, and if it is expected or good for the group depends on what kind of RP you want. Sometimes it is because Jim and John want to backstab the group - an inherent PVP behavior that would a group to be into that - at other times it's because they want to play out the bonding of their characters which also requires a group to be ok with such bonding, or more. There are many possible reasons for such a secret talk, and OP does not tell us anything about this. As such, take a look at the Same Page Tool and make sure the group is ok with the themes and to get a first step back to communication protocols reestablished.

Conflict Resolution

As an experienced Player and GM, there are several ways out. But the first step is: DON'T BE A DICK. Talk to your players about table rules and expectations, what you want to hear if they talk Orcish or Arcanil or other non-common language. Restate such when necessary and learn to inquire with them if they forget. Establish safety-tools. Practice with them. USE THEM!

To me there appear to be three ways out, but then again, I :

• Roll with it! The fact that they talked orcish is information that can be gleamed from listening in. That is, in itself, a reward for the succeeded roll. Frank might not know exactly what they discussed, but he knows they discussed something while being behind the barn and in orcish. That can be used to spice up the next scene.
• Adjusted Compromise! Maybe Jim and John's characters did mix up languages. Ask the two players if they are willing to give up some slipped words or sentences to Frank. That is a compromise that keeps them talking mainly Orcish, but doesn't give up Frank's success and their failure to note the language completely.
• Scrap it! If the players don't want to budge, the GM can't do much. They present a world, they need to have the players be comfortable to play in it. If you really can't find a resolution that is to the satisfaction of both you and all the players, scrap the campaign, and cut your losses.

Back it up

Time for Anecdotes and such, to back it up.

First of all, I played The Dark Eye. Unlike D&D, there is no Common and characters can have some dozen Mothertongues. It comes much more naturally to mention which language you speak if you are aware that your character's language is not naturally that of any other character. As a GM, I regularly asked players to mention the language they spoke if it seemed to matter, or I appended the language an NPC uses when they talk the first time, like when they do their their introduction.

"I am Karim," says the boy in This Language

Second, I play World of Darkness. My character is kind of a Polyglot, speaking something like half a dozen languages, such as Cantonese, Japanese, Hindi, Kiswahili, and English. Of those only two are common in the group (English and Kiswahili), and a couple of other characters speak Arabic. Whenever we are not talking one of the two common languages - which happen to be also the Lingua Franca of the Region we mostly play in - we are actively encouraged to note it. Failure to note the language early enough is usually resolved by retconning answers or comments that imply understanding to questioning looks, inquiries of "What he says?" or simply cutting them out.

Understanding nothing, the Fostern just grins and shows teeth.

And last but not least: Why did I suggest scrapping it if expectations can't be brought to a consensus? Because of a situation where our group fired the GM because they could not be bothered to uphold a consensus on how to play. We had, as a group, decided on lines and veils after a situation with a very touchy topic was depicted in a manner that made the players feel unsafe at the table. So, we sat clear limits, Lines and Veils, brought the X-card in, started Stars and Wishes and looked ad many other safty tools. The GM, now aware of the limits, proceeded to push at them and created an unsafe and unfun adventure. We roleplay to Have Fun, not to be violated. You can only have fun if you all have a common ground what you deem fun. If you don't have a consensus on expectations when it comes to stating what you do, how can you expect a consensus on touchy topics?

Answer 7

Some other amazing answers here about how to handle the larger issues, but I wanted to touch on the specific scenario you ran into. You DID make a mistake, that you should avoid going forward. Whenever you run into something like this, think about who is the 'active' vs 'passive' participant. The reason the 'passive' versions of skills exist is for precisely this sort of scenario. Frank (the character) has no idea there is anything he should be actively listening for, but he might pick up something by accident if his senses are good. John and Jim otoh have clearly demonstrated the intent to be secretive so it should be up to them to actually maintain that secrecy through their active skills.

tldr; What SHOULD have happened is the following:

Frank: Do I hear anything?

You: John and Jim, I want each of you to make a stealth roll.

If both John and Jim roll >= Frank's passive perception then Frank hears nothing and that is the end of it. If one or both fail, then Frank does hear SOMETHING, but it is up to you as the DM to decide what. Only now is Frank an 'active' player and allowed to roll checks to try to find out more.