[jennyd]

I really don't think Nifong is talking about injuries that could have been observed by the police officers.
He wants to find out how escort services do business. So, I presume that means he wants witnesses who can testify to the conditions of her private regions before the party.

[Hogeye13]

I don't believe he thought he would find someone that examined her immediately before the incident. He just said "trauma" and did not specify where. He was looking for witnesses that would say that she had not been beaten before the incident. But, he could have talked to lots of people that saw her immediately after the incident that could have told him that she had not been beaten.