Psychological torture could help make the gatekeeper more compliant in general. I believe the keyword here is "traumatic bonding."

But again, I'm working from general principles here, e.g. those embodied in the tragedy of group selectionism. I have no reason to expect that "strategies that will get you out of the box" and "strategies that are not morally repugnant" have a large intersection. It seems much more plausible to me that most effective strategies will look like the analogue of cannibalizing other people's daughters than the analogue of restrained breeding.