The
odds of that happening to a single player facing AA given that they have KK are higher than one would think because even though an AA only happens about once in 221
hands, if you are playing a 9-seat or 6-seat tournament then that ups the odds up to 9 times that. So, a KK losing vs. AA would happen roughly every 28th time you have KK at a tournament in a 9-seat table tournament. That would be at least one time in roughly 760 tournaments where you are given at least two AA hands yet lose to a KK twice in the tournament.
Given those odds, I'm sure its happened to lots of long-time pros, if not most of them.