I have to faciliate a panel discussion on quality assurance. Any ideas on questions that I should ask?

The panel is comprised of my entire QA department as well as Managers and Directors of our telephone customer service department. We monitor their representatives for quality assurance. Our goal is to have a frank but fun discussion about QA, our relationship together, best practices and any challenges we face. I already have quite a few questions but could use some suggestions. Thank you all!