I was looking for more than a repeat of the question. But actual suggestions.
Due to Jesus' resurrection the Girl would end up with the Lord. The man then has the rest of his life to repent. If the man doesn't, God gets the glory for his patience. If the man does, God gets the glory for his mercy as well as a soul snatched from the devil. Jesus setup a Win win situation.
Should God have struck down that Rapist? Would you have had a problem with a God who does that? Why not punish the man for eternity for what he was planning to do as well. That would be a Win, lose. But perhaps it would be better if the girl goes on to add many souls to the Kingdom, assuming God knows the man would never repent... who can know?
Or God could preempt the temptation, go into the Rapist's mind, and fix it so he would no longer be tempted to sin. But then God would be the Rapist, in a spiritual sense. That is not in his character.
Doesn't your God strike people down anymore? That's Old Testament, right? Yeah, well what about this.
Ananias and Sapphira
1Now a man named Ananias, together with his wife Sapphira, also sold a piece of property. 2 With his wife’s full knowledge he kept back part of the money for himself, but brought the rest and put it at the apostles’ feet.
3 Then Peter said, “Ananias, how is it that Satan has so filled your heart that you have lied to the Holy Spirit and have kept for yourself some of the money you received for the land? 4 Didn’t it belong to you before it was sold? And after it was sold, wasn’t the money at your disposal? What made you think of doing such a thing? You have not lied just to human beings but to God.”
5 When Ananias heard this, he fell down and died. And great fear seized all who heard what had happened. 6 Then some young men came forward, wrapped up his body, and carried him out and buried him.
7 About three hours later his wife came in, not knowing what had happened. 8 Peter asked her, “Tell me, is this the price you and Ananias got for the land?”
“Yes,” she said, “that is the price.”
9 Peter said to her, “How could you conspire to test the Spirit of the Lord? Listen! The feet of the men who buried your husband are at the door, and they will carry you out also.”
10 At that moment she fell down at his feet and died. Then the young men came in and, finding her dead, carried her out and buried her beside her husband. 11 Great fear seized the whole church and all who heard about these events.