a lounge dragon at the DUS SEN lounge once refused to let me in as a guest of another SEN, because "both the host and the guest have to be on the same flight".
Not as weeroesque as your encounter, but after all, a true weero experience has to be the worst possible...
I got that one a few times in the past ... and it also is an unpublished 'rule'.
But if you can argue with the warden, then the situation is not nearly as bad as if you get stuck outside with the moat dragon whose sole job is to disincentivize folks from entering the lounge.