Nolan didn't buy that woman's facade. It seemed so artificial the way she was acting though he wouldn't call her out on it. Who would suddenly draw their weapon against someone and claim that they were an evil witch. It would make him look like a mad man in the eyes of the people around him and may even alert his target. So without a word, he followed Penny though he didn't take the same precautions of emitting his own magic like she did. When the situation does arise then he will strike without mercy.