This game was specifically started to play this RPG, it is what everyone signed on for.
I asked him to specifically take over this game, and asked if he was willing to continue it, he agreed too.
He knows why everyone, except for the one guy, is in this game. I didn't ask him to take over in order to push his own personal agenda, I asked him to take over to fulfill my promise to these guys to run this specific RPG for them. The only people showing any interest at this time in his other preferred games is the one guy who decided he doesn't like this RPG, but stays in the game because he likes the "adventure" as well as the other players, and one other guy who dropped out long ago. So 3 of the 4 remaining players are in this group to play this specific RPG because they like it, and the GM in question frequently swore he loves it as well.
So I think it was completely in poor taste to even ask the others if they want to play something else, when he knows darn well why the majority of them are even in the game to begin with.
So he is breaking his promise to me, and totally ignoring why 3 of the 4 others are in this game to begin with.