And when they asked her who had done the investigation to confirm this she responded that she had nothing else to say. Haha
Exactly. She did her job by not answering the question.
Anyone with knowledge of the law would know that as a prosecutor she can't answer every question asked of her BY LAW. She must refrain from making extrajudicial comments that have a substantial likelihood to cause public condemnation or give extra insight into the investigation that is not necessary to inform the public of the charge.
So if she answered that the state (some investigator) or the FBI viewed the tapes - it would be delving into the investigation and bringing to light the guilt or innocence (likelihood prejudices of the public) of the accused. It's a no-win situation with morons in the media that spin an omission to an answer.