OSX Workgroup Manager

I have a OSX issue that I was wondering if you could answer
The environment is as follows:
1.​​The OSX server is now not bound to our AD
2.​The Mac clients are joined to both AD and OD
3.​The OSX server is also a printer server for the Macs
4.​The OSX Manages the clients Dock settings, Maps shared drives, adds printers
5.I have created groups in OD to manage all the clients

The AD accounts don't sync to OD, so i exported from AD and imported into OD - ​That's fine

The Issue is that all the dock settings that I want to manage will not apply to the client after startup, even though the Client is in the correct group
The reason ( I Think) for this is that the ID or ethernet Mac address is not showing up in OD Group once the computer has been assigned to it

We have some other Macs that have not been re-image so I know the OSX managed settings are working

Is there a way to scan all machines from the workgroup manager so i can add them in the groups without having to copy them from the AD side.