I recently watched Beyond Utopia which featured a different pastor who helps people make it out of NK. He briefly goes in to the human trafficking aspect of the underground railroad, but even just seeing how it all happens, it shouldn't come as a surprise that some of the "good guys" are also abusing those poor people, and not only those who are openly there to exploit them.
The only solution is to be rid of the dictators and states that create the conditions that not only enable but encourage this to happen, for their own gain.