Correct - through the CLI one could see that the old VM that had been migrated from Host1 to Host2 was still showing under Host1, whilst the migrated copy was showing as running on Host2. Once the Host1 remnant of the migration was removed that cleared things and XO correctly reported the VM as running on Host2 with its disks attached.

TLDR - There were no other conflicts beyond what appeared through XO to be the only version sitting halted on Host1, but through the CLI one could see the halted copy on Host1 and the running copy on Host2. Somehow the running version did not show in XO until the remnant was removed.

Thanks for your help @olivierlambert

@olivierlambert Ahhh, ok. Was focusing on XO; that's pointed me in the right direction. Thanks...and have a great weekend!

@shorian No worries. I just figured the full error log would be beneficial to @olivierlambert and team if they review this thread.

Edit: This thread seems related