We are getting into some very complex stuff now. Policies are complicated and often vary depending on the specifics of the situation in question.
Note that I use "ban" and "block" pretty much interchangeably. The action of blocking is used to ban someone from a wiki (temporarily or permanently).
In this reply I'm going to talk about "local issues" - ones that happen on one or a limited number of wikis, and/or don't break the Terms of Use/Community Guidelines. And "global issues" - ones that affect and disrupt multiple wikis and/or do break the ToU or Community Guidelines.
Staff rarely get involved in local issues. There are exceptions when we think an individual wiki needs help.
In the case of this wiki, the ToU issue that brought Merrystar here was an issue with protecting too many articles (ToU: "You further agree [...] Not to intentionally block, remove, or otherwise obstruct the proper functioning [of the] user interface and functionality").
And then I was asked to help when Merrystar ran out of time. I stayed around because the wiki looked to need help with admin issues. I've been mostly gone after that, unless I get a message to or see a ToU issue again (I was messaged about this thread, for example).
On the Moranis incident - that happened a year ago! It looks like he has moved on, although he didn't remove bans he made at the time. I suggest moving on here too. it seems he has not caused problems over the last year (as far as I know), and has not broken any global rules.
The sort of pointless bans he made back then are not outside the ToU. They are considered a local issue. Admins can ban for any reason (even stupid reasons) and are answerable to the community of that wiki rather than to FANDOM.
This thread is about the ban on this wiki. Users are allowed to contact the blocking admin via Community Central to ask for their block to be removed or make other requests. They might also ask someone else they think might help, like another admin from the wiki that banned them.
As far as FANDOM is concerned, users are also allowed to have more than one account. However, a local or even a global ban may be necessary if they use the accounts for abusive things like voting multiple times on a community vote.
If that happens, or if a wiki has a local policy against multiple accounts, then that is usually local issue and the person is usually blocked from that wiki. It's generally more serious issues across multiple wikis that merit a global ban.
Other things:
Aunty7: no, I'm not going to block Moranis/MechQueste - These would count as local issues (probably, depending on other circumstances) and there's nothing that I think needs a ban after so much time has passed.
4Paws: as far as I can see you have never been blocked on Community Central. If you had been banned, that would be by an admin or staff. MechQueste was able to block on adventurequest.wikia because he is an admin there. He cannot block on Central, and as I say, I don't see any blocks set on your account on Central - can you give me more info on this?
Meterman80: He was trolling to get back at those he felt had unfairly banned him. The actual bans were irrelevant (as none of those banned had or wanted to edit there), they are just a year old remnant of the dispute.
I think that's everything answered. As always please let me know if you have more questions and I will do my best to answer (note: I am away most days for the next few weeks, so may be slower than usual.)