Sorry, I missed that this was not your Core machine that you migrated.
Nevertheless, even a remote will have a program state that is saved in files on the remote’s machine, and maybe this can be backed up in an inconsistent state as well if the backup is made while the remote is running. There is not very much lost when doing a fresh install of a remote, and I don’t know if it’s worth backing up. Though I have to admit I’m not sure if import settings, which can be quite complex, are saved on the core or in the remote. I would guess the core, but have not tried this.
You can try uninstalling Roon on the new machine and then deleting the migrated program folder that contains the info of the Roon remote. Reinstalling Roon alone is probably not enough as I don’t think this program folder is deleted by this. All this saved Roon info that belongs to the remote should be in your user account’s applications library folder, User > Your username > Library > Roon. Try moving this to a different place (to have a backup just in case), create a fresh Roon install, and redo your remote settings.
The user library folder is hidden by default and you can make it visible as described here: