There was a play near the end of the half where Romo threw out to Barber. The officials ruled incomplete, and Barber fell on the ball.
Cam Cameron attempted to challenge the play. Why? I have no idea. Let's suppose the ref had allowed it. They would have reviewed it and found it was a lateral that was recovered by the Cowboys. Miami would have lost a timeout, and the result would have been the same.
Now its possible he was trying to get the officials to pay attention on the field, and it wasn't about that specific play, but come on!