Hello @Tim
I know it might be a stupid question but did you join the computer to the domain? I am sure you went trough a guide to join the other computers but check the guide below and ensure that Group Policy has updated.
Join computers to the new Windows Server Essentials server1
https://learn.microsoft.com/en-us/windows-server-essentials/migrate/join-computers-to-the-new-windows-server-essentials-server
Hope this helps with your query!
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