Please recall that Czechoslovakia was essentially sacrificed by Britain’s Neville Chamberlain in return for “peace in our time.” The Czechs, then, had to live in submission to their Nazi overlords. People in those circumstances sometimes have to make agonizing choices.
The last 2 sentences are an attempt to shed some light on that...the SS realized their time was coming, but wanted the “work” to continue. How to do that when they are telling the SS guards and such to make their escape?
They conscripted many “regular” folks to keep it going. I would suspect there was probably a few SS diehards willing to stay behind and make sure it did...