Some people have reported problems with Hubitat discovery of Sonos devices even when everything is in the same vLAN and subnet--so that could be the problem, but it's possible the fix won't help. Assuming your hub is indeed able to communicate with them, you could try manually adding them if you don't want to rely on discovery (which it appears may indeed need some additional work like you posted above to work between the two). Here's one post on how: