Custom flags shouldn't be submitted if raised through review audits

I'd be very very wary about ignoring custom flags. They can be used for all kinds of things. Perhaps, though, they should be clearly marked to show the moderator that they came from a review audit, which would allow the moderator to dismiss as helpful unless the text of the flag is something unusual.

People may use custom flags to point out a pattern of a user's behaviour, for example, and such custom flags should be evaluated by a moderator, even if they were raised on a post in a review queue.

However, if the flag is clearly marked as having been raised on a "known bad" audit, then the moderator can read the flag and, so long as its concerns are confined to the post itself, just dismiss it as helpful.

I don't think it's safe to ignore a custom flag, even one raised during an audit. This post might have been a crystal-clear case of spam/abuse, but in other cases a user could decide a custom flag is really needed, maybe to report that deleting the post was wrong, or that it isn't so bad it should be used as audit (which happens more often than I would like). And there could be other valid reasons that I can't think of now.

Ideally, I think it should work like this: if the user chooses a custom flag during an audit, he should be notified that it is an unexpected choice, because a normal one should be enough, and moderators should be called for only to deal with unusual situations. Then the user gets a second choice: in light of the explanation of normal vs custom flags, does he still want to raise a custom one? If he decides a normal one is enough, good: he learnt how to use flags, no one was disturbed, he passed the audit, and everybody is happy; otherwise, the custom flag is sent to moderators, who check it as usual. If there's nothing that justifies* it, the user should learn that he chose the wrong flag, and it should be declined. And the audit should be considered failed. The user did get a very clear and specific warning after all!

Otherwise people will keep raising custom flags for everything.

If this second screen is too hard work, I'd say the flag should be sent to mods, and if it is not justified*, it should be declined. I understand you didn't want to punish him, but the fact is that he did something wrong, and the right alternative was very easy. If no one tells him, he'll keep doing it.

*To clarify, if the custom flag is "This post has been flagged as spam, but it isn't, there is indeed a link to a product, but the user states he is the author", this is what I'd call a justified custom flag, even if the moderator disagrees (for example because he thinks the disclosure is not clear enough). What I'd call unjustified is a flag like "This post is spam", "It's offensive", "It is not an answer", and so on, things for which we already have normal flags.

I think this is related to the recent bug, which as I mentioned before, seems to be caused by flags failing to act like they're happening as part of a review.

I find it very, VERY hard to believe that you would only be noticing this now if it had been around before. In fact, I remember trying to flag an audit before with a mod flag, and I failed the audit (I thought it was plagiarized from the top voted answer, but it was that answer :P).

Some earlier answers support this.

I just got an audit, and I'm going to see if I am able to submit a mod flag on it. For science!

It appears to have worked:

Interestingly enough, after I flagged, the "I'm Done" button became enabled, and I had to click it and I passed the audit.

Note that they are going to fix the flag bug soon. I suspect that this issue will be fixed with it.