WIM restore error code 60 - help!

Created Bootcamp image on my iMac pro using 8.2.
Partitioned drive on another iMac using disc utility.
Went through restore process - getting error code 60.

Have tried it twice…any suggestions? p.s. - I am restoring to a lager partition on my my new machine.

This is the bit of the Log at error point

Creating files: 273500 of 711692 (38%) done

Creating files: 274000 of 711692 (38%) done

Creating files: 274500 of 711692 (38%) done

Creating files: 275000 of 711692 (38%) done, exitCode=60, NSLocalizedDescription=WIM-based restore failure with error code 60}

2020-05-20T15:43:26+01:00:Setting the system to allow sleep…

2020-05-20T15:43:56+01:00:Mounting Error: An timeout occurred when mounting /dev/disk0s3. Please check that you can mount the volume in Disk Utility and try again

Additional Info: Error occurred at TCSPrivHelperToolController.m:497
2020-05-20T15:43:56+01:00:Mounting Error

Is it possible the volume is unmounting in the middle of the process? I have had issues with drives that have heavy usage unmounting and causing this error.