That doesn't answer my question. First off, this is Server 2016 1607. Second, Security / Windows Defender shows the app has been installed from the server, which is good. However, C:\ProgramData\Microsoft\Windows Defender\ exists, as well as HKLM\Software\Microsoft\Windows Defender and all of it's subkeys still exist. Under C:\ProgramData\Microsoft\Windows Defender\, Platform contains two old versions of Defender. These are detected as vulnerability.
I guess the best I can do is, after removal of the "feature", I have to manually delete C:\ProgramData\Microsoft\Windows Defender\platform and HKLM\Softwware\Microsoft\Windows Defender\ InstallLocation & BackupLocation keys. Everything else cannot be deleted as they are locked by System.