Run this script on one of the affected machines under the user who was used to perform the RUM processing.
(Get-ChildItem -Path 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Print\Providers\Client Side Rendering Print Provider\Servers').PSPath | Join-Path -ChildPath 'Monitors\Client Side Port' | Get-ChildItem | Remove-Item
Restart-Service spooler
If the workaround is successful, you can then add it as a post processing script in the RUM move task configuration.