If he is truly a member of the Latin Kings, I'm sorry to tell you, but NOBODY will be fucking with him in prison.
Dude, you haven't been watching every single prison show on TV for years with fascination like I have, have you?
The blacks and whites will both fuck around at will with whoever they're told to fuck around with. No one is scared of the Latin Kings (at least they can't admit it) if they're in with their own gang.
There are guys in prisons in every state who can and would stomp AH into the next life.
If you're ever sentenced to prison, start that day a.) eating everything in sight, b.) lifting everything in sight, and b.) growing a badass mustache. If you go in scared, there's one thing you're going to be doing: whatever the guy you're scared of tells you to do and that'll probably be sucking dick for favors.