It depends how you define a political prison camp. I hear in the testimony of other political prison camp survivors that the degree of the punishment, isolation, and torture is a little bit different. In the case of Camp 18, it is not a total control zone.
As they said, a real political prison camp may be defined as a total control zone. I hear that even in the Yodok camp, there are two parts. One is a total control zone that you can never leave. We don't know how they are treated because they are destined to die in there. Nobody knows, because there are no survivors so far. For other camps, maybe after years, after serving their term, people can be released. We have survivors.
Generally, labour camps, whether they are total control zones or not, we still think of as political prison camps. In that sense, I don't agree with him that there are no political prison camp survivors; there are, I guess.