Ash Roberts
So - thankfully, I had taken steps to make sure that I COULD get back into my VM. Prior to removing the certificates, I had unencrypted the drives, turned off TPM and tested rebooting successfully.
What my REAL problem turned out to be, is that I was trying to do this process on a host running server CORE - which will not allow you to remotely export the certificates with a private key. I had to find PowerShell commands to allow me to do this whole export/import process from the hosts.
I also found that I could re-create my certificates from PowerShell as well. In case anyone else finds this useful, what I did is below.
I found the existing guardian:
Get-HgsGuardian
I then removed it:
Remove-HgsGuardian -Name "UntrustedGuardian"
And finally, I recreated the Guardian with the certificates:
New-HgsGuardian -Name "UntrustedGuardian" -Generatecertificates