That's the whole point. Trump doesn't hang out with slick lawyers who know all the right weasel words to stay out of jail. That's why he won and not Hillary. None of Hillary's people would make silly public statements against a prosecutor and would therefore not be labeled "nutcases".
Mueller’s job came from a chain of events that based on the phony “dossier,” so why wouldn’t he blackmail characters like Nunberg to suborn perjury? But it’s possible that Nunberg is trying to diminish his own credibility as a witness.