Another 73 year old fart here… You appear to have ended up with different versions of Roon on different devices. They all need to be at the same version to talk to each other.
First, what are you trying to achieve? To have all your devices running Roon 2.0, or have them all running 1.8 Legacy?
Once you’ve decided what you want, read this article for the steps you need to take.
You have my sincerest apologies for the delayed response here, we’ve been dealing with a higher-than-usual volume following our release and we’re working as quickly as we can to get back to everyone.
After reviewing your account, I see that both your roon remotes and core are all on 2.0, are you still running into issues?