Redirect to Other tab from Custom tab/iframe

[AmandaDavis]

We have embedded our iframe into a custom tab within the Candidate entity and everything is working well. We’d like to have a link on the last page of our iframe to re-direct the user back to the corresponding credential in the candidate's “Credentials” tab but we need a url to do this and have not been able to get this to work.
Has anyone had any luck with this?