I just talked with Don on this issue and after some investigation of my own. We came to an agreement that we do not believe it's possible with the current Microsoft RD client for macOS. Don believed that in an older version of the client it was possible but the latest version of the client didn't release any documentation on switches or options that could run with it. After some research, I too couldn't find any reference to it.
Edutainer Manager, ITProTV
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