Allow Service Desk customers access to private Service Desk KB's

Service Desk allows users to have KBs linked to Service Desks. However, the customers in the new billing model cannot be given permission to Confluence and will not be able to access the KB unless it is public.

As a user, since this KB is directly connected to the Service Desk, I'd like to be able to have my customers access the KB, even though it is private. Either allowing them to access Confluence somehow, or only the KBs.

Partial work around

Where possible a 2-legged OAuth applink with a real Confluence user specified can be used to restrict access to Confluence while maintaining search functionality for Service Desk Customers. All searches will be made as the user specificed in the "Execute as" text box in the OAuth application link configuration. The application link cannot be use 2-legged OAuth impersonation as Service Desk Customers do not have Confluence user accounts.