Edit: The factory reset went fine, both handsets were found and the
phone app recognised it as a Quest 2.The PC software is still apalling
and the link still doesn't work, but at least I know that the reset
isn't automatically a source of problems.
Have you tried PC programm > setting > beta > retstart Oculus? That
worked for me. You could download the support folder, rename the Old
support folder support.com install the new support folder and see if
that works for you. If not it's easy to reve...