Super frustrated by the same thing.  As far as I can make out, the fix is to [install cloudflare warp][1] directly on the vm (which appears not to have a headless login method).

The problem with piggy-backing on the windows instance of cloudflare-warp is that it sets itself up on loopback, and from my quick investigation, the VB instance can't route to that listener.  There may be another path to success in fixing that route/connection issue.  I'll keep poking at this and will try to remember to update here if I find a fix.


  [1]: https://developers.cloudflare.com/warp-client/get-started/linux/