I gotta do my due diligence and source this but I think there was a podcast called the "truth and justice podcast" that found a interview with the head of police before Jays testimony that said the police had located the vehicle and were withholding the location from the public at the time.
This means the police already knew about the whereabouts of Hae's car before Jay. This part gets slightly more conspiratorial but the police could have lead Jay to the car instead of the opposite.
Agreed, it's possible. Though we'd also need to explain why Jay is still sticking to a made-up "I buried a murdered woman" story decades later. And find the "real killer" who happened to murder Hae the same day Adnan loaned Jay his car and phone...
(PS: You can bypass the paywall to read parts 2 and 3 of Jay's interview by disabling Javascript.)
This means the police already knew about the whereabouts of Hae's car before Jay. This part gets slightly more conspiratorial but the police could have lead Jay to the car instead of the opposite.