I don't get it. Why not use the Ford Coyote engine with a supercharger? That's essentially what they did in 1971 when the Pantera was born. It would make the car affordable.
I believe that it is because the car is not a ground up build but a re-bodied Lamborghini . This is so that they are not required to recertify the car for emissions /crash testing etc... like they would with a new car build .