Some answers, but likely not all.
First, you may have some WiFi interference causing connection issues between your Move and your Ray. I’d suggest a network refresh, by unplugging / powering off both Sonos devices. While they’re powered off (or unplugged), reboot your router. Wait a couple of minutes before powering back on / plugging back in your Sonos, so your router has time to boot up. Once the Sonos devices are showing up in your controller again, check for updates in the controller. It will check for both controller updates (your devices) and the firmware (the player part on the speakers).
This might fix your disconnect issues between the two, and your ‘unable to group sometimes’ issue.
The lag issues between the two devices is concerning. There always will be a small lag when a TV input playing on the Ray is grouped with the Move, but there never should be any lag when you group the Ray with the thing playing on the Move (the turntable, or any other stream). I’m not sure I understand why this would be happening when you play a turntable input, only a TV input from the Ray.
I would recommend that you submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it. Don’t post the resulting diagnostic number here, they get sensitive about GDPR.
There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.
When you speak directly to the Support staff, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.