OK, last weekend I turned the key. Turns over fine, doesn't make any weird noise, starts to catch and dies. Longest it's run is ABOUT half a second, maybe less. Sounds great for that half-second.
I panicked after my compression test because I got numbers between 0 and 85. BUT...looks like the valve stem is trashed. Tested with my air compressor. Pulled the valve stem out so I can't get 100% accurate numbers but I can say that every cylinder bounces up to 120 cold with a closed throttle plate. That's enough that compression isn't the reason.
Fuel pressure hits 50psi while priming, maintains about 45 while cranking.
Pulled the spark plugs and they spark while turning the engine.
The only codes are 4 for the TGV and 1 for the EGT. I'm under the impression that TGV codes MAY trip a limp-mode that limits RPM to 4500, but that none of those will cause a no-start.
I haven't hacked up the harness yet, but I did pull remove most of the airbag stuff, rear hatch cord, and rear radio cord so I could stretch the harness out far enough. I did bolt down every ground I could find (maybe 7 from the main harness and all of the grounds on the engine harness). Installed the ground strap from a starter bolt to the frame. Big fat negative cable bolted to the frame, but the 3 inch negative cable is loose.
Wifey has a video because I was hoping for a first start. As soon as she sends it to me, I'll link it.
I'm going to go dig through the manual, but if anybody has ideas, I'm glad to hear them.