Delete "Recovery Points Only" using Remove-EsxVirtualMachines does not work since they do not have a protectedserver.
How to delete them using powershell?
Use the powershell command Remove-RecoveryPoints instead, i just tested it and even when the machine is in recovery points only status worked for me. Here is the direct link: Rapid Recovery 6.3 - Command Line and Scripting Reference Guide (quest.com)
Let me know how it goes