What probably happened is pretty simple. The singers always do a dress rehearsal of their songs before the live show goes on the air, and the judges probably attend the dress most of the time, and start taking notes on what they're going to say on the air. Poor Paula, in her pills-and-booze haze, just confused the dress rehearsal with the live show, and started talking about songs that hadn't been performed on the air yet. Don't judge her. The same thing would happen to you if you did enough drugs in your workplace.