That's the only reason why Ash would bring Charizard this time.
There is a rampaging Garchomp in the first episodes. I say that is a good chance to bring him back. Considering the fact that they brought him back for nothing in Unova. They may be warming the kids up for something like that.
I'm sure he won't be brought back because of this. If there's a raging Garchomp, why wouldn't Ash have already sent out Charizard? Why is he relying on just Froakie and Pikachu? Unless Charizard is slightly out of camera angle, it doesn't make sense that he would have Charizard in its Pokeball and not use it against Garchomp from the start.
The Official Bulbasaur of Pokemon X's board Bowser Jr, T Zelda, Ridley, Palutena, Pittoo, Isaac, Shulk, Mewtwo, Robin, Balloon Fight, Crono, Mii, Megaman, Neku