Removing the Authorization Server can be done with the mzsh mzadmin/dr topo unset command.
Run the following command to remove a single instance of the Authorization Server service.
mzsh mzadmin/dr topo unset topo://services:<standard/custom>/obj:<service>.<service-instance-name>
Example - Removing one instance of Authorization Server
mzsh mzadmin/dr topo unset topo://services:custom/obj:oauth2.oauth2-instance
If you have multiple Authorization Server instances, you can remove them all at once with the following command
mzsh mzadmin/dr topo unset topo://services:<standard/custom>/obj:<service>
Example - Removing all instances of Authorization Server
mzsh mzadmin/dr topo unset topo://services:custom/obj:oauth2