How to restrict Service Assignment Queue maintenance to Queue Owner using data security

Summary:

We have a business requirement where queue managers should only be able to view / update queues where they are assigned as the queue owner. This includes managing resources within a queue, as well as updating the queue owner. We have created a custom role that uses a Data Security Policy with a custom SQL predicate to restrict the access to queues based on who the owner of a queue is. Despite the role being provisioned, and all other roles being removed that would grant access to other queues, the user with this role can still see and make updates