Not sure if this is the exact video/transcript you are looking for, but here is what I think you wanted:
Starting at 1:35 talking about the sighting (or transcript posted below):
http://www.youtube.com/watch?v=eaWmdLnm7qA
GRACE: One more thing I`ve got to ask you. You have told me, and we have asked police, and they tell us they cannot confirm it, that a neighbor sees your daughter Hailey in your backyard around 12:00 noon, talking on the cell phone. That would be the Monday. The Monday she goes missing.
But police say they have tried to verify that, and they cannot. Are you positive? And what neighbor is it?
DUNN: He is actually living in a neighbor`s house. I think his name is Charles. The man that owns the house is Travis. But he told us that he seen Hailey in the backyard and he said he told police that also.
GRACE: OK, because we have asked police and they`re telling us they cannot verify it. And if that`s true, that means that nobody absolutely can positively say they saw Hailey since the night before at 10:00 when you saw her watching TV.
That changes the whole -- that`s a whole new ball game if we cannot spot her. Your son comes home, your 16-year-old comes home at 4:00 p.m. the next day, Monday. Hailey is not there. The boyfriend is there.
And your son says he beats on the door, he can`t get in, takes him five minutes. He has to get in the house, nobody will let him in the door, and he sees your boyfriend and your boyfriend he says has a deer-in-the- headlights look. This is at 4:00 p.m.
But Miss Dunn, I did not invite you on tonight just to rake you over the coals about these various inconsistencies about the New Year`s Eve party. I want to hear what you have to say tonight.
DUNN: Well, I wanted to come on to clear some of that up. I don`t want to be perceived as a bad person even by people who don`t know me. But the main reason I am here, I don`t want people to get away from the fact that the whole reason we are here and we are talking to media is because my 13-year-old daughter isn`t in my house. Somebody knows where she is.