So trying to PXE Boot from a newly created VM in Hyper-V wasn't as straight forward as it was supposed to be.
This all due to the way Hyper-V displays its GUID.
Entering the GUID (as-is) will not work if you are creating a prestaged computer in Active Directory. The reason for this is that the GUID displayed by Hyper-V is in GUID string form. Normally during POST boot screens the GUID displayed is in Octet string form, but Microsoft decided to switch it up making users scratching their heads.
So with Hyper-V, make sure you add the brackets when entering the GUID for created the prestaged computer.