Does the original content get preserved in the revision history if the suggestion is used? If not, it should. That way, others can check if there are issues with the suggestions and roll back if so / understand what the original question was.
Upon further thought, I could see how this could be complicated, since the suggestions can be chained multiple times, with manual changes between each "round". I still think this is worth considering. Each time a AI suggestion is accepted, just take any manually-made changes and give that a PostHistory entry attributed to the PostOwner, and then give the AI suggestion a PostHistory entry attributed to the AI.