Maybe I'm just a vindictive asshole, but agree 100% on suing for the damage and/or the deductible on the uninsured motorist coverage, even if they don't have the money to give out of pocket. Getting your money back over time is better than not at all. If they're only asking for the deductible, that's small claims court and doesn't require a lawyer or a long lead time.
The problem is that the insurance companies will always lowball you.
your friend needs to determine exactly what his losses are (including increased premiums over the next years, rental cars, medical costs - in short, everything to put him back to where he was before his accident.
If there were injuries, then it becomes even more difficult to put a $$$ on it.
My advice is - don't be greedy, but make a list of all of your financial losses.
that's the same advice I gave to a friend of mine who was hit by an "under the influence" driver this past Sunday. Five people in their MDX - all injured - ranging from broken wrists and sternums to our friend with two broken ribs and a lacerated liver.
The driver that hit their MDX told the cops he wasn't involved and tried to walk away, then came back to get his wallet - but apparently forgot that his (also totaled) car was in his name and he was limping. He is in jail facing four felonies and a handful of misdemeanors.