Documenting the changes for future and however is silly enough to use Opensuse & Roon.
Well, the roonbridge service was added:
In YAST, set firewall to Permanent instead of Runtime.
Add the [roonbridge] service (was a very very small + icon bottom LH corner
Add the ports from this post for Roonbridge, thanks to @japhet_martinez for the ports to open:
TCP/IP Ports 9100-9200
UDP Port 9003
TCP/IP Port 52667
TCP/IP Port 52709
TCP/IP Ports 63098-63100
TCP/IP Port 49863
After restarting the firewall, then adding roonbridge service to the public and home locations, Roon Core and the other windows PC could see the DAC connected to the OpenSuse workstation, hurrah!
I could hear the click from the DAC, but no sound. Tried another DAC, both USB and not a peep.
The detection of two DACS is working for Roon Core, but the local ALSA is not working, so driver problem.
Linux is an ass.