From what I've read -- and note I am not stating in any way that I know all the facts -- when the girl left the track she didn't know the extent of the injuries suffered. Anyone holding her at fault is doing so without knowing all of the circumstances involved.
Also, the mere fact that she later showed up at the sheriff's office without being sought indicates she wasn't trying to hide or "get away." And bringing her father with her was a smart move, again indicating a certain degree of maturity that some people here seem to be denying her.
When I was in the military (I was definitely on our side!) I was once serving as the gate guard at a missile facility. One of the guys who lived off post was late, and when he arrived in someone else's car he jumped out, ran behind the car and directly across the highway without looking. A 16-year-old girl who'd had her license less than 30 days hit and unfortunately killed him. Her mother was in the car with her. They stopped on the shoulder of the road, but did not get out as the Army medical personnel were already on the scene. They rushed him to a civilian hospital about a mile away, but it was too late.
Anyway, as I recall it the Military Police, along with the local authorities, quickly got the girl's name and information off her license and EMPHATICALLY told her mother to take her home in an effort to lessen the emotional trauma she was already beginning to experience.
Her court date was about three months later. I was the primary witness to the accident only because I knew the guy was late and was looking for him.
There were one or two others who'd seen part of it. We had a brief discussion with the city attorney before the trial actually began. When we walked into the courtroom the first thing the city attorney told the judge was that he wanted to drop the case as this was clearly an unpreventable and unfortunate accident. He essentially blamed the victim for his own death, which was actually what happened when he tried to run across a busy road without looking. What I was particularly impressed with was the attorney's wish to not have something like this on the record of a totally innocent teenager.
Since the soldier's parents never tried to institute a lawsuit, it must have been the right decision, and we should probably assume that the girl's decision to leave the track was also the right one at the time.
Jon Asher