I saw it too. She plays it on her current shows. She was NOT "pushing for a confession", Nancy asked this woman where she spent the day that the baby disappeared. She refused to answer. It was more than obvious that the mother did NOT want the child found.
Grace is pretty dramatic. It seemed to me that Grace was accusing her of being responsible for the childs disappearance. I remember the girl refusing to answer, but the insinuation was there that because she refused to answer, she was guilty. The question was whether the child was dead or alive. All in all, I think Grace will win this.