Quite a long post, but I took a little time to read the OP's post. It seems I don't have the capacity to express an opinion here. But I would like to have a little opinion.

For advanced identification, it sounds good. But if the moderator has to see the PM and publish it to the forum then I think that's too deep and the PM is someone's secret. Everyone has secrets and I don't think it's ethical to share anything in PM with the public

Note: PM privacy is not guaranteed. Encrypt sensitive messages.