If Hertz can't handle a simple rental transaction correctly without calling the police and resulting in a false arrest, I'm certainly not going to trust them to handle a car sale correctly.
If Hertz botches it so badly that the state paperwork cannot be correctly filed you will find that out shortly after buying the car and can get it corrected.
It shouldn't even get as far as the prosecutors. 5 mins of policework should get to the bottom of the matter.