Condolences for the loss of your friend.
We had a older cyclist run down in the wee hours by a hit and run motorist a year or two ago. It took six to nine months, but they did find the person and charged them. I didn't follow the case to see what the results were.
Maybe they'll find the culprit in this case too. I'll probably start running cameras front and back so my family will know more exactly what happened to me if my demise is to be while cycling.