I agree with your characterization, but I expect both your comment and this to be removed because we are making a personal accusation. I know that beating around the bush would not put such a fine point on it and call out the actual users who are exhibiting the problematic behavior, but for the good of the community discourse, personal call outs need to be removed.
so while I agree with your characterization, you need to try to communicate it without publicly making personal attacks.
no. an ad hominem is attacking the person instead of the argument. regardless of the truth. poisoning the well is a great one, as it is an ad hominem that usually features true accusations which are irrelevant to the discussion. which could also be called a "red herring" (but most fallacies are doubly red herrings)
whatever that means. if they used two separate accounts you wouldn't even know. how about you just address or ignore each comment in it's merits, and stop trying to control other people.
I went back and reread it. you called them a troll.