I've been asked this question in a few other places, and I'll respond the same here as I have there:
I consider the reason why Newt is no longer part of the GDM team confidential, similar to how we don't share why someone is blocked (note: leaving a global group and being blocked are, of course, two different things).
However, if there is a decision your wiki is trying to make where you feel this information is relevant - for example if you're trying to decide whether to give Newt local rights, or remove rights, or how to deal with a situation involving him - I'd advise this: Make your decision based on the contributions he's made to your wiki, just as you would if he were any other regular community member. This should be the principal rule in any community decision, even if the user was or even still is a member of a global group.
If you tell me why you need to know, perhaps I can give more specific advice.
This is not a reason why Newt shouldn't be welcome on the Disney Wiki. He can be a local moderator here, or even an admin, if the community wants him to be.
The Inheritance wiki doesn't have the quiz feature enabled yet. But once it does, why not re-create your quiz there?
https://inheritance.fandom.com/f