Let's break down this video a bit.
The police ask him to leave because of his not wearing a mask. IMO, people are assholes if they don't wear a mask while being asked to do so...but again, not necessarily illegal or enforceable. A business can ask someone to leave, however. And, they can do that for just about any reason (there are reasons that aren't valid, like if someone is asked to leave because of their color of their skin, but in general...business wants you gone, you go). But, that leads to the second point.
The cops ask him to leave because "they want you to leave". That works for a private business, but the post office isn't a private business. It's a government institution and are considered public property. Public property isn't necessarily open for anyone to do anything until it is breaking the law, however. It gets murky. There are "limited free speech zones", and the post office may well be one of those. But, in any event, the officers can't justify a trespass on public property simply because "they want you to leave".
I don't give a shit about the military terms that the police use. The US isn't a war zone. Usually, police departments have a policy that when a citizen asks for a supervisor, that one is called. The cop he was talking to said that he is a supervisor, but he is not his own supervisor.
The guy threatens a multi-million dollar lawsuit and that the officer will be fired. Yeah...almost certainly not. It's possible that he would get some kind of payout (10k?), but not much and the officer most likely wouldn't get fired. Meh...cops are allowed to lie. I'm OK with this boastful exaggeration other than that it makes him look stupid.
The auditor is correct that if the reason they are kicking him out is because of his camera, that the Rules and Regulations Governing Conduct on Postal Property (poster 7), specifically give him permission to film in there. He is also right that they can't kick him out simply because "they want you to leave". In fact, it's possible that the local police don't even have jurisdiction in that post office unless there is a written agreement between the post office and the local police.
The whole mask thing, I'm unsure of. If that was the reason they kicked him out, I honestly don't know how that would play in court. Was it during the time that Biden's mask mandate on federal property was in effect? If so, possibly it would work. If not, I'm not sure how it would work.
The narrator's fat jokes, fart jokes, etc...really don't add anything.
The auditor was clearly a jackass. No doubt.
The auditor was an idiot for challenging the police to some sort of martial conflict.
The auditor is an ass to everyone that talks to him, but then again, he's right that he owes them absolutely no explanations nor do they have any ability to stop him.
I had to stop watching. I could stand the narrator less than the auditor. Pretty poor video and reaction video. I give the auditor a D-. The reaction video creator, an F.