The problem with exercises is the fact that many of them would not apply to your business. Try this, instead:
Collect 3-5 cases of recent quality failures, customer complaints, things that kept you and others at the company, awake at night. Things that have cost your organization not only money, but reputation and good will with customers, as well.
Now use those real-world, relatable cases and have group discussions on how effective internal audits could and should have been conducted which could have either prevented or mitigated such quality problems. I have done that exercise a few times and at the end of the group discussion, some people had a much better idea of what effective auditing was supposed to accomplish.