I don't think so by strict RAW but I think it works by RAI.
Grit, luck, and panache represent three different means by which heroes can gain access to the same heroic pool, using it to accomplish fantastic feats. For characters with a mix of grit, luck, and panache, they pool the resources together into a combined pool. (Those who use panache and luck gain twice their Charisma bonus in their pool.) For feats, magic items, and other effects, a panache user can spend and gain luck points in place of grit or panache points, and vice versa.
I don't see why a character who has panache and luck would get twice Cha to their pool while a character who has panache from two different classes wouldn't.