Good morning Roy,
My cousin searched around for bereavement boards. She didn't find a board devoted to her situation. She did, however, encounter others who had similar experiences. If memory serves correctly, she came across a post from another grieving mother, who had recently lost her daughter in a car crash. They really did help each other out, even though their daughters died under different circumstances.
Remember, this was 12 years ago and now, there are more available resources than ever.
Have your friends been in touch with Victim's Services? Are they getting any counseling? Your friends probably need all the help and support that they can find. You are indeed a good friend for trying to help them during this time of need.
Warm regards and best wishes, TrueHeart