I think it is just a statement of fact. I’ve read that the work camps had much higher death rates than the Jewish death camps with the furnaces. Perhaps it was the total number of deaths, as there were way more work (slave) camps than death camps. They would work them to death (or killing them when they could no longer work) and bring in more.
I believe there was a stone quarry in, or near, the complex, as well.
I agree. See my previous to gundog. My mistake.