Do all of the roles show up in the uc_roles_expiration table, or just the one? It seems like if they are all getting set in the database, just not being reported in the order or user areas, then it might not be the function isn't working - maybe it's just the reporting that isn't.

If you create a new role and a page that only that role can access, you might need 3 pages (one for each role) - and check to see if you can access all three pages. If so then it looks like all 3 roles are getting assigned.

Just scattershooting here.