Thanks for the tips above. After many attempts, I found that removing the device from appleid website worked, I had tried earlier with iCloud and find my devices, but no luck that route.)
Here is what I did. I setup a USB installer with 11.1 installer.
Ran recovery and disk utility. Deleted the Macintosh volume and the Data volume. Recreated the Macintosh HD partition as APFS.
I also did the recovery terminal and resetpassword to remove my ID from the actual hardware.
Started the USB installer going. While that was running, I removed my new MacBook from the AppleID device list.
When I got to the country selection, carried on as normal. Connected to my Apple ID. Then created the local account as normal.
Waited. Didn't think it had worked... then BOOM... it did. Thanks for all the tips. This was a big relief after a frustrating day!
Issue seems to be with Apple not able to renew an existing Apple Device on your Apple ID. You'd think they'd test this stuff.
Glad they could be of some help.
I finally got my initial issue fixed - iCloud Drive syncing. Took awhile to get to senior support, but after some guessing and checking they kicked off a 'health check' on my account and *poof* everything started showing up. Not quite ready to fully commit to this machine, but we're a whole lot closer today than I was a week ago.