North Korea is so tightly run that I don’t think that would work there, instead of injecting a political virus into their society the NK government would merely imprison or kill anyone who came back mentally impure, and they would exam thm upon entry, NK doesn’t play around and allow the seed of anything to start or even arrive, NK is impossibly isolated and controlled.
You’re probably right. Those that volunteer to return home can be returned at the DMZ after a bus tour of Seoul. Dental implants for those missing teeth. Cameras everywhere.