I'm telling you this because I am taking care of the 3rd Seat, but I get interrupted at each publication by your edit. So please leave that Hibari-like general alone some minutes so I can get it right.
Then, explain me: What is the problem with Mange Tout?
It is the kind of things I am usually not concerned, and I still don't see your point.
I understood that you were recruiting for a group, but I am clear with that: I deny the proposal, and find myself out of concern about internal things of the group. And I doubt I'm in any power to make anything about one.
Then, I get the problem. You fear that the SKIA admins search about Mange Tout's vandalism and ban him.
Well, I'm sorry to say that I can't do anything about it. I can't prevent an admin to search about him, I can't prevent someone that know about it to tell an admin. Still, I understand your worry.
Your subordinate "repented", right? He stopped vandalising the Wiki, or doing similar things? It may play in his favor if he changed since the time. That's my opinion. Else, I don't see anything to do.
Edit: Yes, I am here. It takes times to me to read and answer.
Edit 2: After reading the rules of the site, I see clearly why they would do that.
So there is few risk of him getting banned. If it is relatively unknown, if there is too few people to tell about it, and that it happened nearly 3 years ago, then you don't need to worry much about it.
Just do in sort that he doesn't do it againt anywhere else.
Well, I don't know about a DM function, but it sounds improbable to me that he gets denounced by 5% that might gets his IP about something that happened 3 years ago. I think those 5% turned the page since a while.