I solved the mystery of the inventory cars. According to the SA I just spoke with the cars are assigned to the locations as they are built so they aren't necessarily there yet but they are on their way. The SA couldn't even see the car in his local inventory although when I search by my zip it shows it is local. Still doesn't explain the assignment method but I definitely would not recommend anyone order a car at the beginning of a quarter unless they want to prepare to wait a long time for it.