Presumably because that's what she's been told even when she questioned on it. And what she was instructed to say. It doesn't necessarily mean she actually believes it and on the basis of DU's behaviour I'm sure, like most of us, she is rapidly coming to the conclusion that many of her instructions are going to turn out to be flat wrong /lies if not illegal. But if she hasn't actually seen the emails then all she can do is take her client's word.
Actually beginning to feel slightly sorry for JR.