2003 Dodge Caravan Van won't start - multiple things alread

Had an issue a while back with my 03 Caravan not starting. It started out with one or two missed starts, then eventually got to the point where it won't start at all.

- My first thought was starter/solenoid, so I replaced those. (This is one of those 2-in-1 deals where the solenoid is part of the starter. I am NOT a fan.) No luck.
- Towed it in to a mechanic, he said it was the TCM and wanted 1,000.00 to do it, but gave me the information to try it myself.
- Ordered a new TCM, had it flashed with the VIN/mileage/etc, installed it today, no luck.
- Tried swapping out relays, no luck
- Checked fuses, they're all good.

A couple of odd things:

- There are two wires going to the starter on the bottom; one is in a harness and connects to the solenoid, the other just screws on to a bolt on the starter. I put a voltage tester on both of them and the one in the back has a constant 12V, while the one in the front (that connects to the solenoid) has nothing, even when the key is turned to "Crank the damn engine already!" Position.
- When I turn the key to the "On" position, all of my dash lights come on, then go off as normal. Then when I try to crank the engine over the "BRAKE (!)" Light comes on, even though my parking brake isn't engaged. This stays on for about 3 seconds, then goes off, which makes me think that it's an indicator of. Well, something.

My Google-Fu is all tapped out, as is my bank account at this point, thanks to all these shiny new parts. Any suggestions/pointers are welcome.