You’ve probably already read suggestions about the Smart Hub. I have the first version of Smart Hub but despite having UPnP switched on, I had to set it up manually, entering the port number 55000 under the Roon ARC tab, and the following in the port forwarding section in my Smart Hub:-
Michael
PS I wonder if there’s something in Windows stopping it working for you? I use ROCK on a NUC so don’t have a Windows firewall in the way.