at every start hybrid battery SoC is 24.71, no matter SoC when shutdown..?

OK, hopefully someone here can help me narrow this issue down... my 23012 third-gen, w/ 280k miles, is giving me seizures over the hybrid battery... here's the deal:

I have two sets of hybrid battery modules, when one needs work I drop the other one in so I can take my time fixing... a couple of weeks ago I saw that Dr Prius was displaying that block 6 was 1.4v below all the others in the pack consistently... under load block 6 would sit unmoving, or spike high as the other blocks do their work. when charging it would spike way above the other blocks and the Dr Prius app would color it in red. when starting the car I'd get an instant Hybrid error every time. so I pulled the pack of modules and swapped in my spare set. fire it up, and...

...instant hybrid error. so I'm like Wth, what is it now? check w/ the doctor and, damn! block 6 is still doing the exact same thing! what are the odds??? I pull the spare pack, immediately go buy two more modules from a local reseller (who does actually load test etc), tear it down and swap both modules making up block 6 w/ the new ones.

sigh. problem solved.

not.

block 6 is still doing the exact same thing. and this is when I realize, no matter what SoC I'm at when shutting down, every time I next start the car it is at 24.71 SoC. every time. so instant Check Hybrid System error.

I replaced the sensor harness last year preemptively because the original showed lots of corrosion/buildup, but regardless of that I am assuming the persistant bad reading on block 6 must be either sensor harness or BCM, correct? but the resetting of SoC at every startup, can that be from the BCM? I'm kind oif at a loss right now, I don't get it. I've checked the BCM and all cables/sockets/pins for any obvious scorching or damage, but they all appear fine visually... I'm going tyo pull the harness and attempt to test continuity (and impedance?) w/ a multimeter later today,but does anyone have any ideas as to what is giving on w/ my battery? any suggestions or insight would be most welcome friends..