Hi @Keith_H_Wofford,
AirPlay 2 is not supported by Roon. If this device also allow for AirPlay 1 playback then is can be enabled and used in Roon.
We have information in out Knowledge Base about enabling devices. Go to Settings > Audio and click enable for the Apple TV device.
If you don’t see this device in Settings > Audio please let me know and we can do some additional troubleshooting.