Re: Using Set-VMhostfirmware or some other cmdlet for a restore

I was expecting a MismatchedBundle fault.

The Set-VMHostFirmware -Restore cmdlet uses under the covers the RestoreFormwareConfiguration method.

And the MismatchedBundle fault makes it very clear why your action won't work, mismatched UUID.

Now you could consider zapping the UUIDs in the bundle, but that would be a hell of  a lot of work since the bundle layout is not specified publicly afaik.