Radio is working. It was a blown 20a fuse under the hood.
As for the wire, I'm not 100% certain where it should be attached. Should I just solder it to the area where I think best? May need to solder a patch wire to increase length a bit. We'll see.
2006 Pathfinder LE: A battery jump went bad when the negative jumper was connected to a metal pipe causing smoke and fireworks on the other side of the engine while superheating the jumper cable connections. As a result, a green wire where the smoke originated became disconnected (ground to AC pipe?...