I get what you mean, he wasn't a bad person really, he was trying to do what was right, and when Billy first really got in trouble it was because of the same. I could still kinda see him ditching Billy and Mach maybe. probably not very likely, but hey, i wouldn't exactly want to come back to an island that in about 30 seconds was about to be crawling with bloodthirsty beasts hunting for the nearest warm blooded meal, either. I'd have to really care about the people I was going to get. I think his actions according to this will be hard to determine until we figure out just how close he and Billy are, because i don't think he'd come back to that island if he didn't really have a reason. I wouldn't.