I still think it was one of his buddies playing a dirty trick on him. Pretty easy to make fake documents on a computer, especially if you have no idea what they are supposed to look like. If the complaint really came from the DA, he would have been visited in person by a police officer or a DA invesitgator.
This has hoax written all over it . . . note that the poster gives a statute that refers to the penalty for the "crime," but not the statute referring to the crime itself. One would think that a misdemeanor complaint would notify the accused what statute has been violated, even in Wisconsin.