Proper way to remove Defender from Active Directory

All - I have been asked to "properly" decommission Defender from our Active Directory environment. It has not been in use since sometime in 2018 (I am a new employee). None of the servers with the Defender software are around any more to do an uninstall if that is how to decommission this from AD. I could just delete the OU but there seems to be deeper ties into the AD schema because if you right-click any OU you and click  "New" there is an option for "Defender Token Organization Unit"

Any advise is much appreciated. Not sure if just deleting the Defender OU is the only option? Just looking to remove all traces of the product out of AD.

Thanks!

Don