Sonoma screen sharing bug

My first Sonoma (maybe) bug. Tried to do a screenshare from Crozet, VA (Xfinity) to Cville, VA (Xfinity) - about 20 miles, and which I had done several times before.
Me running Sonoma, remote running Ventura.
Remote received request, replied affirmatively but I got a refusal. I moved to a Ventura system here in Crozet and it worked fine.
Additional data point: did a screen share on my home network (me: Sonoma; remote: Ventura) and it worked. I am suspecting this is due to me having credentials on both internal systems