Thank you for posting your question. Unfortunately there is no way to work around this. You have to have the user as a member of the local administrator group on the WSUS server.
Thanks for your response.
It's a very bad new for us...
Quoting from the SCCM documentation: "All System Center 2012 Configuration Manager site systems must be members of a Windows Active Directory domain." The server with the Software Update Point role must be a domain member. I'm not sure how you could have even installed the role on a machine that is not a domain member.
You aren't trying to connect to a standalone WSUS server, are you?