Can't start my 2011 Lexus ct200h, 'check hybrid system'

Hello,
I have read hundreds of threads in this forum, and others including the ct200h forum, and tried every suggestion I have seen and everything I can of, multiple times over 3 days, but nothing changes.
Problem:
When trying to start the car, green light is on on the start button, hit the start button and the ready light flickers for about half a second, and then all instrument panel lights are on similar to if you turned it to 'Ignition On' mode by not pressing the brake pedal. When I reset everything by disconnecting 12 volt battery, disconnecting white wire, unplugging Orange safety plug, and waiting 15 minutes, and then try starting, the ready light comes on and stays on for 20 seconds or so and then it goes back to the same state. The gas engine never runs. I have taken the cover off the hybrid pack and checked voltage, which is 201.1V. I checked all groups of 2 cells, and the lowest measure 14.1V.
It occurs to me that it might be dying and ready light going off right when it tries to turn over the gas engine. Could it be that the hybrid battery doesn't have enough juice to turn the engine over, or is something else wrong? Also, there is some corrosion on bolts of each bus connection (as seen in attached picture), but maybe that is normal for a 14 year old car.
Background:
Car was running rough last fall, so it sat for the last 8 months. I removed the intake to clean egr passages and changed the plugs. Now car won't start. I double checked and triple checked all connections. I replaced 12v battery with new. Trickle charged both batteries to 100%. Tried jump box and jumping with other vehicle. All lights come on instrument panel. Light on start button is green. But car won't start. Get message to check hybrid system. Hybrid battery graphic shows only one bar.
There are no codes related to the hybrid battery. Current codes are B126a, U0100, B2312. The hybrid battery worked great when it last ran.
Thank You

 

I had to go out of town for a couple weeks, and then I waited for a new obdii scanner to show up, so I finally just got back to the car today.
Thank you for the response, bisco. I can't find any damaged wires, but I haven't dug into everywhere.
I tried a third new 12V battery, and a fourth large deep cycle battery. Nothing changes with either. It seems the ready light might stay on a bit longer with the large battery, but it might just be my imagination. Regardless, the gas engine never turns over.
I used the DrPrius app and the Hybrid Assistant app, but I'm not sure I know anymore than I did before. It definitely looks like a couple cells are worse than the others (matches what I saw with the multimeter). As you can see in the images, after an hour and a half of messing with it, the pack voltage dropped 7 volts. I did get code p0a0d occaisionally, but not always, and no other codes.
If there were a damaged wire, would you see any of these results? If the inverter was bad, would you see any of these results?
Any ideas?