"Those guilty of slander will be held accountable..."
This isn't something a lawyer would say. Even a bad lawyer understands slander refers to verbal speech, not written words.
Moreover, the crux of determining civil liability with slander or libel is that the contentious comments must be UNTRUE.
So Troll-hating Dominguez is one.
Additionally, it is a civil matter so “guilt” would not be the correct term. It would be a case to determine whether the defendant is liable.