Could be. As I say, the info isn't hard to get. A pimp would be the kind of person who would readily know how to get the information or who to go to, whether he had any dirt on the person or not. It's also not particularly expensive.
I think too much is being made of the question of Mangum's ability to get the information. It's not at all difficult, even for an unsophisticated person like Mangum who no doubt has a lot of street smarts, as you say.
"Mangum's ability to get the information"
Would any (Duke's) student records be available at another (NC State) university - say for instance student loan info?