File signed agreements, keep order receipts, bundle handoffs. Every one is ready to run, and you can adjust it in plain language.
Remove flagged, unapproved members and report access blockers.
Keep your discussion channels aligned with access reviews, and give reviewers before and after member lists.
Close approved message removal requests with a dated case result.
Your reviewer sees whether a reported Google Chat message came down, with a dated result on the removal case.