Hm. I'll pop over to the Cabin Crew forum and ask there - it does seem as if it was that oh-so-rare incident, 'rules' being made up on the spot or incorrectly remembered by someone with whom one Must Not Argue.
I sometimes fantasise about carrying a little notebook around with me to write such things down as they happen to me (as one did earlier this year, where I was effectively threatened with arrest for photography on a main street in the USA), and where the unarguable one can be asked to append their name, rank and signature.
It would be confiscated in seconds, of course.
R