I never do the audits. Too hard. It is not a trick question. If it asks you to acknowledge that the assignment is both a mystery shop AND a revealed audit, then it is the audit. The answer to the question is YES, because the audit is both. You start out like a mystery shop and it then turns into an audit.
Be glad you were disqualified. I'm sure some people like the audits. I personally like the mystery shops, but I think the audits are too much work for too little money.