Ok, thanks for the clarification, @lupu is already working on a fix - we probaly found the restore issue.
Another approach I’ve used in the past when merging domains onto a new server is to restore the backup as a temporary user, and then move the domains / mail domains / databases from the temp account to the target account. Then you can delete the temporary user.
But it seems the Hestia team have provided a fix in the code now.