Looks like Julianne Moore and John Cusack are confirmed/rumored to be in The Hunger Games: Mockingjay - Part I, which comes out later this year. Maybe Crucial BBQ is just really excited for the movie and good at memorization?
As for me, I have been trying to avoid using TV shows because I'm not sure if it's against the "rules" to use them or not. Including TV shows could also make things complicated. For example, if the actor only appeared in a single episode in the entire series, do you have to give the name of the episode? What if the actor was in a few episodes but not necessarily a main character?
Edit: I'll just add that I think you can do whatever the hell you want. I think this is meant to be a fun way to pass the time while waiting for admission decisions. Calling other people out for something that's against the "rules" seems to be missing the point of the game. But that's just my opinion.