Check to see if the dude has a not insured motorist clause, then he could get his money but the insurance company will more than likely go after your friend, but at least insurance companies will take a payment plan settlement as some money is better than no money in their book.
Also, your friend could call around on estimates of repairs, as an ex auto tech I highly suggest he call auto parts shops for any body parts (aftermarket), the only way I would put factory is if the vehicle was less than 4-5 yrs old. Painters will not like you supplying your own parts, but they do know that work is work and everyone has the freedom to choose where they want the repairs done.
All in all though, your friend is in a bind, I would first get estimates (they are free) at some shops just to make sure the dude is not trying to rip your friend off. Sounds like this guy does NOT want to go the insurance route and is trying to get more money for himself. The dude cannot harrass your friend, and the worst he can do is go crying to his insurance company. If he does that then yes, the insurance company will be dealing with your friend, but at least they are more professional.
Of course in Texas insurance is mandatory, so we do not have many uninsured motorist accidents, and the cops do not bother finding faults, that is for the insurance companies to do.
Like I said, that dude cannot do anything himself except for small claims if he chooses to not go through his insurance. Advise your friend to get honest estimates, and then call the dude's insurance company and talk to them, as sooner or later he will have to deal with them or a court.