Yeah, it's really lame how they just kinda vanish like that. And you never hear about them again. The only time you do is if you happen to go into the Returner's Hideout after the island goes up into the sky. One of the guys in there will ask you "How is Banon" (or somthing). I've always said "I don't know, YOU TELL ME" outloud cause I'm a dork.