It's at 12.7v between the power cable and the ground cable at the amp. As far as the headunit goes, I checked the accessory and the power lines in the back of the HU before the inline fuses. The accessory line gave me 0v, and the power line gave me 12v. The HU can't be turned on though, not even by pressing the power button on it.
I took readings on the accessory line with the key turned to accessory, and with the engine running, both were 0v. The amp didn't turn on when I shorted the power wire to the remote. Does it look like a problem with the accessory line itself? Or did she just manage to fry every piece of audio equipment in my truck at once?