Its a bug, slaves cant level at all, not even trappers. i've had them kill gecko's for a half an hour and nothing happened.-Ulrek-
I know, what i'm trying to say is its a bug, they're all meant to level, so you asking for XP to be given to the owner of the slaves who cant level would be using a feature to cover up a bug. since all the slaves are meant to level. so when thats fixed all the slaves will be able to level, and your suggestion won't be used due to that.-Ulrek-