Another indication that Jay is working off of the maps in the police file is Jay's odd confusion over the name of the street Jenn lives on. Jenn's house was off a street named McAdoo, but when the detectives ask him to name where she lived, Jay answered, after a couple hesitations, "Conway."
Problem is, no only did Jenn not live on Conway, there's also no Conway street anywhere near Woodlawn. Jay could not have been thinking of some other Conway street, not unless he was confusing where Jenn lived with some street in downtown Baltimore.
So where does Jay pull the name Conway from? And why, in the interview, does he sound as if he is struggling to read it?
Again, the maps hold a clue. The name of Jenn's street is not identified in the maps in the police file, but there is a restaurant that is located almost right over where Jenn's house would be, if it were depicted in the map:
The restaurant is called "Canopy," not Conway, but seen from across a table (or perhaps even upside down?), it could be confused with Conway. Or at least, I made the same mistake, the first time I glanced briefly at the maps to check the answers Jay was giving. Only later when I looked again did I realize that Conway was not there at all -- it was Canopy, and it was a restaurant. Not hard to see how something similar could have been going through Jay's mind, if he was trying to answer the detective's questions based on the maps in their files.