Manual config of Sonos not working

Yes, I have an advanced network setup… :grin: Which is always the first question. I have Hass running in Docker, connected to 192.168.2.0 segment. This is connected to the 192.168.0.0 segment with SoftEther on a server to server bridge. That should transmit everything needed. But even when I add the Sonos manually in configuration.yaml with the adress 192.168.0.213 it doesn’t show up in Hass. 192.168.2.213 does. I would think that it at least should show up as Unvailable, or something, but it’s just nowhere. Is there a “force manual setup” that I’m overlooking, or something?