If I were doing the floor and not know what the manufacturer recommends the last thing I am doing is putting PT wood in there. The PT wood needs to dry and will bring moisture to the plywood. I know there is a lot of weight involved but I would worry about warping.

I would just swap out the PT wood for rigid foam insulation sheets - 2 inch variety. You can get really large sheets at the big boxes in the US. This will taking care of minor moisture issues and offer an escape route out. Also it might give the dance floor a slight bounce.

If I were doing the floor and not knowing what the manufacturer recommends the last thing I am doing is putting PT wood in there. The PT wood needs to dry and will bring moisture to the plywood. I know there is a lot of weight involved but I would worry about warping.

I would just swap out the PT wood for rigid foam insulation sheets - 2 inch variety. You can get really large sheets at the big boxes in the US. This will taking care of minor moisture issues and offer an escape route out. Also it might give the dance floor a slight bounce.