On user objects in Active Directory, the memberOf attribute is hidden by default. In order to get access, IT pros or AD OU Admins will need to complete FERPA training, available at http://registrar.illinois.edu/training-ferpa. After doing so please submit a ticket to adsupport@illinois.edu requesting access. 

After approval, the requestor is placed in a privileged access group "UOFI Registered Service Accounts", which has read access to the memberOf object on the User class.