Well, that's sad. If you wanna attempt replacing the h/w, I did a little searching around and found (again) the youtube N9 disassembly video I used when I needed to replace N9 screen and battery. (It's very good.) By about 7.5 minutes in he gets to the micro USB connector. The heat gun he mentions in the beginning is not required to get to this point, but a hot air soldering station will be to remove the surface mount port, which he describes as "Qui' uh tricky job". I think I'd remove the speaker while doing the desoldering work.

I haven't seen an N9 specific USB desoldering tutorial, but there are generic USB connector swapping videos that should help.