If they evidence is right and General Motors really did know about the ignition switch flaw before her death, then yes they could have prevented it from happening. There is evidence that shows that not only did they know, but that they also purposely tried to hide all evidence that they knew.I believe GM caused the death of that young woman.
Yes, GM could have prevented the death of Brooke Melton, because they could have put out a warning call for that vehicle much sooner than they did. It took her death to lead to the recall. There was an ignition switch flaw, and that happened in many other vehicles. She was not driving too fast for conditions.
General Motors knew of the problem with the ignition switch ten years prior to Brooke Melton's death. They have not been honest about what they knew and when they knew there was a problem. The data recorder of the car shows that the car switched out of run and to accessory just before the crash.
I think that GM could have definitely prevented the death of Brooke Melton. Had GM take better measures and safety precautions regarding their products, they could have ensured that there would have been less of a chance and risks apparent to some of their customers. GM can be blamed for his death.