Remote WDSUtil and "the user has not been authenticated"

Running Windows 2012 with WDS installed. We have a script that works locally. However, I cannot figure out how to execute it remotely from a non-WDS server. It comes down to the WDSUTIL command, when executed remotely via PowerShell like:

Invoke-Command -ComputerName $WDSServer -Script "WDSutil /Remove-Image /Image:MyTestImage /ImageType:Install /ImageGroup:Windows2008"

always returns:

Error Code: 0x4DC
Error Description: The operation being requested was not performed because the user has not been authenticated.

I tried specifying -Credentials and -Authentication but did not find a working combination. How does one execute WDSUtil remotely?