I think the AV did quite well, by the looks of the picture.
Think about it.. almost 5800 lbs and the roof line and front doors appear to be minimal or no damage from a frontal impact. I take it that there was no intrusion into the main cabin area. The front end collapsed and took all the energy from a 5800lbs load...
As for 3 star for driver and 4 star for passenger, I could only think that the drivers feet would have suffered more injury. Steering wheel mechanism, brake pedal, gas pedal, emergency brake pedal etc.. But at least you would survive.... I would like to see a picture of a collision between the AV and a mid size car.....( lab test only, I don't wish to see an actual impact )