confused on some points

Would appreciate clarification on a few things. As I followed it, I got:

1) wife cut off son's penis

2) dad then had his own penis cut off - I thought he was doing this sort of in solidarity with his son, and out of guilt that obviously HE was who the wife really wanted to trim.

But from other comments, and then later in the movie it seems the son has a penis. So the dad's was transplanted to the son? If the son had a new penis (from dad), why was he presented as if he didn't have one? I'm thinking of the scene at the police station, and the way guys tried to take his pants down to see, and how he couldn't piss right. Was it just that they could see a scar and wanted to see that?

In the gang rape of the convenience store worker, I was under the impression he was going through the motions to save face, and had no penis to rape with anyway. But if he did have one, did he actually penetrate/rape her?