I'm not convinced Gale is being all that truthful in all the stories he tells. I've finished an evil playthrough with him in the party and he will go along with destroying the grove, as long as the evil PC passess an insight or deception check. Even though Gale initially tells the PC he'd sacrifice his life to save others, in reality he is willing to do whatever it takes to survive, if you can convince him. The deception check is a bit funny; it's basically the evil PC telling Gale: You want to leave? Dare you.
