That sounds ridiculous. I was under the impression that they test every board at the factory before shipping it out. There shouldn’t be any DOA unless someone on there team is wet stamping the inspection operation.
Unfortunately, there are not a lot of options for high power bms’s.
its totally clean, like brand new clean.
So what i did was tear into the pack itself again and this time i found a few things. it looks like the balance wires had intermittently started shorting and one of them cooked inside the insulation until it was no longer conductive. Ive actually seen that happen in front of me. The superworm type balance lead wire has insulation on it that can take those kinds of temps breifly, and breifly is all the wire can handle so the short cooks the balance leads copper like a fuse and leaves the insulation intact. When it happens it looks like a light is walking through the wire on the inside, then its gone. Which is way better than that crap insulation on the balance leads that come with the BMSs, that stuff just melts instantly almost and would probably cause another short. Anyway between that and some other weirdness the whole pack is basically useless. I’ll probably save the good P groups and cobble together a short lived beater battery out of them at some point.
So i guess this wasn’t exactly like the last time.
So nothing wrong with the bms then? On one count of battery slaughter, we the jury find the defendant mr. BMS, Not Guilty?
yeah apparently the BMS was fine. Just the cells were screwy.
Its so weird.
Perhaps it was a rogue cell that took out the whole parallel group.
Probably a foreign intelligence cell.
Did you get your 18650s from Russia? 
Its possible the spy cells have infiltrated US distributors, we’re going to have to assume the worst and go to DEFCON ZERO. EVERYONE IS BURNED. TORCH YOUR BOARDS AND PHONES. OBTAIN RUN BAGS AND MEET AT PRE-ENCODED RENDEZVOUS POINTS. THE PACK IS PUFFED. I REPEAT: THE PACK IS PUFFED