If they're trying to shame or chastise others, while being wrong, seems fair to me. Then again, I subscribe to the "play stupid games, win stupid prizes" school of dickish behavior correction.
Or, to defer to the ever-wise Gods of the Copybook Headings:
"What's good for the goose is good for the gander".
I've noticed that if you stay strictly professional, folks think higher of you and they feel shame for having done this. You also appear way wiser and likeable - all of which gives you more clout. And if you're more often right than your peers, everyone benefits by your having more clout.
I've been in this situation before and I've found this approach beneficial.
And since the boss knows you are right because of your previous behaviour, all you need to do is ask the boss to take care of the disturbing element if it continues.
Or, to defer to the ever-wise Gods of the Copybook Headings:
"What's good for the goose is good for the gander".