Good stuff! I applaud you on your choice to take the time do this.
[quote=“mattesque, post:8, topic:56646”]Every domain failed to copy, and I am not running huge amounts of files – one WP install and maybe a few dozen files on the other domains.
Why did this not work?[/quote]
Jobs like moves are queued, so it might be that the copy script had not run yet.
My first advice would be to “wait a bit”, in case it’s a queue issue.
Simply copy over the folder that each user “owns”. If anything is broken after that you’ll need to determine why, and how best to rectify it. If the sub relies on the domain (or vice-versa) it might be a case that both the domain and subbie are probably better running under a single user - unless you have time to dig into the code in order to separate any such reliance which would be more in tune with your account-hardening undertaking.