I have been informed that as of today, Qubes Windows Tools 4.2.0-1 is packaged for r4.3 and is available in its (default testing) repository. It can be installed in dom0 via:
sudo qubes-dom0-update qubes-windows-tools`
It is not necessary to download the nightly builds anymore (it is still possible if anyone desires to do so).
In the meantime, the test results from the latest openQA run for Windows 11 installation with QWT is all green. Which is even more promising that the test results for Windows 10. Here is the video.