Make notes, maps with dimensions and get pictures
You'll want from him any and all pictures taken and any and all medical evidence.
Don't talk to him either in person or on the phone always write a letter (recorded delivery) or email (use the receipt acknowledgement function).
"We have two witnesses that will" - turn that into have made.
The driver of the car you were in has notified the insurance company involved? They may be able to help or provide suggestions etc.
Start doing searches on the internet to get information about this sort of thing; how and what to do, and to build your confidence.
You are clear: he came out of a minor road and collided into the side of the car you were in? Your pictures of the scene will prove this? Your photos of the damage done to the vehicle you were in will assist in pinpointing the point of impact.
Put a personal support network in place.
File a complaint against the police force involved for failing to attend a RTA (road traffice accident) when advised/requested.
You did get his insurance details?