lol no need to feel bad, you could probably swap the GBA's for normal's anyway..
It would only be a problem if they did breed and any survived, I would say some probably would as by the time they leave the cave they're pretty amoured etc But yeah alot maybe all would get eaten its OTY really, personally I would get myself out of the potential situation before it happened, otherwise you could be faced with having to intentially destroy babies if they did breed any some survived.. And that would probably be alot harder than getting rid of a few now