If the indictment does not state which laws were broken, is it a legal instrument under New York law or not?
Does not matter.
The process is the punishment.
Its not. A criminal defendant has the constitutional right to know what he is charged with. Otherwise how do you defend against it? This faulty indictment is a clear violation of due process. Also, the FEC has sole and exclusive jurisdiction over federal campaign finance cases, not NY. NY can not glom on to something they have zero jurisdiction over, in order to skirt statutes of limitation and/or to upgrade misdemeanors to felonies.