A user that is assigned to the Service Broker User role can see all of the published catalog items, but does not have access to the "Request" button (it is greyed out).
Aria Automation 8.18.1 and older
There is a current limitation where the user interface for Service Broker can only enumerate the permissions for the first 50 projects where the user is included as a member.
Use the "Search" option to specify the project or catalog item