Like what he said, T43z0r. Nintendont only looks for games that uses it's gameID as it's folder name. And Twilight Princess gameID is GZ2E01 for the NTSC-U. You can't use any title name of the folder to reach the game. The name of the folder for that game has to be it's gameID.
Already changed the folder name to that id and it still couldnt find it