Honestly, Newt on a planet full of child molesters isn't a movie I'd like to see. Even with the protection of Hicks, Ripley et al, it's just not a situation I'd enjoy watching or thinking about, it's tasteless.
I agree, so just drop that aspect then. Just make them murderers, etc.. The understanding is those type of criminals go into prison with a target on their back anyway. Even convicts seem to have a code regarding such horrible actions of abuse.
Simple. In real life, most convicts are fathers, and I would lean more toward protection of a child than any sort of group dynamic allowing harm, even amongst a group of murderers. It would have to be someone catching the others inattentive or during an attack or something. The simple solution is the pedophiles amongst the group would be as fearful of reprisal from the fathers/murderers as they would be the xeno. At least the xeno would probably be quick. Probably.
I would assume Andrews would order a quarantine, and with a healthy fear of convicts, Ripley and crew may actually adhere to it until a xeno shows up.
The moment could be hinted as a potential threat rather than being the stereotypical centerpiece,and not have to make it on screen visually. From my understanding of protective custody and classification systems amongst differing correctional agencies, I would speculate WY may not lock pedophiles up on a remote world like that anyways due to the probable "distraction" it would become for the non-pedophiles. You're pretty much guaranteeing an incident. It's true pedophiles are locked up in general population, but there are also specific facilities where state funding allows. Then again, government and corporate decisions don't always approach logic.
Were any of the inmates pedophiles in Alien 3? I would be shocked if any made it through the years following the change of status of Fury 161.