Have I seen this kind of thing before? Yes, but not in softball.
There was a guy I went to High School with who was blessed with incredible speed and athletic ability. Our losing football team coaxed him into joining our team at midseason and our fortunes immediately changed. By the time our offensive linemen initiated contact with defensive players at the snap of the ball he was already through the hole and racing towards the endzone, he'd take one cut in the secondary and race past defensive backs who had an angle on him.
By springtime he went back to his main sport which was the 100 meter dash for the track team. I was also a track and field guy so when the six of us who qualified for the state meet went, our coach was certain that this guy was going be our school's first state champion. The only problem was, he didn't show up for the finals. He was there at the stadium in his uniform with his spikes on and just didn't feel like showing up for his date with destiny. He was just as calm and nonchalant about out it as could be on our very quiet ride home from the meet.
This guy wasn't an arrogant jerk or anything and got along well with teammates in all sports I played with him, he was always pretty much a loner though. Although I lost touch with him I heard he became an alcholic not long after high school.
I don't buy the finances aspect for the reason Bill's player no-showed Nationals. If finances were the reason and the girl really wanted to go, they would have given some hint to that effect beforehand. It could have been the girl, the parents or some combination of both but I think you just got another one of those strange breeds of athletic free agent nomads that wander this and every other sport.