Roon tested only means Roon have had it in the office to test it. The Muso 1st gen only supports Roon via Airplay and thats how Roon plays to it wether Roon shows it as tested or not it doesn’t affect playback. Roon tested incorporates Airplay devices it is not Roon Ready which the latter devices are.
What were you expecting it to show up as? Roon tested devices do not have RAAT connectivity.
USB, chromecast or airplay only
From Roon Ready description
“Roon plays to thousands of USB, Airplay, and Chromecast devices, but Roon Tested devices are profiled by the Roon team to ensure simple setup and effortless daily use.”
Edit: I’ve assumed that “Other network devices” is a sub-group in the “Roon Tested” group, but it could also be a separate group in its own right. In which case the original question from @rhqp stands: why isn’t the Muso QB 1st gen device (which is Roon Tested) showing up in the Roon Tested group…
Perhaps the roon tested section doesn’t include airplay devices? My qb and denon amp, also roon tested, are both listed under “other network devices”. As does my ndx2 (which is also roon ready) for connection via chromecast and airplay.