ᐅ Drywall Installation and Vapor Barrier – A Different Approach

I will have it starting mid-January. It was agreed that the general contractor (Fleischer) would dismantle the drywall to save costs. I figured he couldn’t mess that up. I arrive at the construction site and see Sascha from Ukraine (with no knowledge of German) doing the plastering. I also shared my opinion with the general contractor by phone last night, which resulted in him calling in sick today. So, what should I do now with the unprimed but already plastered concrete ceilings?