First of all, they DID do an audit, that's what a manual recount is. Second, the same reason cops aren't allowed to search your house just because you can't prove that you didn't kill Jimmy Hoffa: you need to have evidence that a crime has been committed. You didn't. Not one vote was fraudulent. Not one. You were asking the court to throw out millions of votes when you couldn't even show one that was bogus. And to this day, YOU keep avoiding THAT.