I read it somewhere. I think on Gamespot or somewhere. But, I could be wrong. They way I heard it was that PD had gotten permission from the racing team to use their car, but not permission from Lambo/VAG to use the brand name, which is why it was just the Diablo GT. But when VAG found out about it they yelled at PD for using the car without their permission and so PD respectfully pulled it.