Just to be absolutely clear about the video, there was no showdown. The loser did not call the winner's bet. That was clarified by floor a couple of times. So he absolutely had no case and it seems like floor told him so.
Regarding a potential rule violation by the winner re talking about his hand:
RRoP says that "Revealing the contents of a live hand in a multihanded pot before the betting is complete" is improper and grounds for a warning (or worse). Key word there, though, is "multihanded". If I understand correctly, heads-up you can tell your opponent you've got anything you like, and so this guy did nothing wrong. In fact, he should be commended for making a brilliant play against an idiot.
Even multiway, though, I'm not clear on the reasoning behind the rule. Under what circumstances could revealing your hand disadvantage one of your opponents? I suppose there's a collusion-like element, where you let one opponent call and then tell the other guy "you should fold, I've got aces". But short of a prior collusive arrangement, is that collusion, or simply favoring a player at the table? Surely you're allowed to treat different players differently, right? Softplay one guy because you feel sorry for him and go all-out on another just because you don't like his face, or his breath, or his politics? Isn't that part of the psychological game?
And besides that, short of actually turning your cards face-up, doesn't the possibility that you could be lying about your hand count for something? Again, isn't that sort of table talk part of the psychological game?