I'm not sure what they're going to do with the traitor plotline. It was only ever speculation from Mic, so there's a chance it was meant to be a red herring, OR Shigaraki is going to cash in on the traitor now or soon after he gets his powerup, right when it would hurt the Heroes most. Still think Kaminari is the most likely suspect. We know next to nothing about the guy aside from him being dumb, sunny, and an all around friendly guy who packs some serious power when he actually gets his head in the game. Also, there is the USJ incident to think about.