I'm sorry but some white sheets + sunglasses is absolutely not resembling the KKK in any way, especially since everyone in the US is already dressing up for Halloween. This seems to be just overblown drama. Some dumbos probably thought they'd make some funny ghost voting video for tictok or something, not knowing the rules. Claiming this to be some sort of intimidation attempt is just a fragile victim complex.
Nope, in almost every context it's fine to dress up as a ghost. A polling station An in person voting location in Georgia is one of the only exceptions.
They weren't allowed to stay because they were filming. I'm struggling to apply Hanlon's razor to you right now, since you sound like you're arguing in bad faith just for the sake of arguing.