[aerohead]

Me too!
Could be that they actually did a 3D-laser scan of the actual car, as input for the CFD software.
A research university in China previously published a CFD analysis for the Tesla Model S, and I believe that they did scan an actual car to get the data cloud.
A college mate, with aeronautical engineering degree from NASA, worked at Southwest Research Institute in San Antonio, Texas. They had a physical, 3D scanning device Glynn used to scan an US NAVY F-4 Phantom jet, then used to operate a walnut shell blasting media paint removal device which 'knew' where the aircraft 'was', incorporating optical recognition software, to ascertain 'when' the paint was satisfactorily removed.
If a car was mounted on a rotisserie, giving the physical probe access the underbody, it wouldn't be a problem to 'learn' the whole car.
It would take a long time though.