I'm currently renaming my systems with the Autounattend.xml, rather than asking TOEM to do it. I think this creates issues with Image Only systems showing up in TOEMS but, it does work.
From my perspective, the computer name should be set before it is domain joined, so renaming via sysprep ensures this happens. There is a great autounattend generator here: https://schneegans.de/windows/unattend-generator/
They also have useful example scripts you can use with the generator here: https://schneegans.de/windows/unattend-generator/samples/
As we name all of our systems according to MAC address, I'm using the "derive computer name from MAC address" script. I am thinking of instead using this script as a TEOM script module that applies before the domain join policy. That would probably make more sense.