What a sad story!
It is unlikely that any psychologist in Philadelphia would give the correct advice, the advice I would give my daughters-"Aim for center mass, and keep squeezing the trigger until he's down".
Recently there was a serial killer in the Baton Rouge area. He has since been caught. I got both of my daughters at LSU Glock 19's with the then hard to get hi cap magazines. They both can shoot well and that is exactly what I told them, Aim for center mass and don't stop until he goes down.
You are right and anything anybody could do in terms of the law getting involved would have been lame. The man should have been picked up and put someplace where he couldn't hurt her but unfortunately it isn't done. I wonder if she knew him, must have. Poor parents, they should have at least got her home safe till he was off the streets.