The only reason why I think he's not an S is he's wacky mental behavior. I'd argue that S's are more in tune with the world. Furthermore, the only ESTP i know is so very keen of getting socially accepted, thus, devoid of any "wrong manners".
He is ESTP. Dont confuse his act with who he is. He plays people and everything is like a game. He lives in confusion and confusing others. ENTPs are to insecure with S to be able to play people like Jack does. The STPs I know so easily fit in that they dont have to worry about being accepted. We can easily act stupid or mental with no fear. ESTPs are known as "players" for a reason