The SAS Web Administration Console is not a SAS Management Console plug-in. It is accessible via the URL http(s)://webhost:port/SASAdmin.
This SAS Note talks about how to add plug-ins to SAS Management Console:
Usage Note 60639: Adding plug-ins to the Application Management folder in SAS® Management Console
https://support.sas.com/kb/60/639.html
--
Greg Wootton | Principal Systems Technical Support Engineer