Laminate in the basement: Lay PE foil despite vapor barrier?

Thank you.

But the PE film, how do I then attach it to the screed? Because if I glue the rubber onto it, it is initially only laid floating overall, isn't it?

And what is the purpose of the Al*jet waterproofing under the screed?

@ Scout: First of all, I have to apologize! I had focused the overall topic on laminate floors, as noted in the original question. In your case, it is stated that a synthetic rubber floor covering is to be glued on a floating screed. I simply overlooked that, please forgive me. In this case, no residual moisture rising from the concrete is to be expected. Here, only the substrate (i.e., the screed) must be ready for installation and sufficiently dry. The floor installer measures this with the CM device. If the basic condition is met, the screed surface can be sanded, primed, and puttied before installation. The PE foil is obviously unnecessary when the top layer is glued! Sorry again! Best regards, KlaRa