Specialized battery BMS dead help

I bought a used, unbalanced specialized 460wh for cheaping just to tinker with it. This battery is unable to be filly charged due to error and only charges up to 87%. Cut the story short i opened it up to Check on the cells. While charging, i was testing the cells with a multimeter when it suddenly turned off and stopped charging. Now it neither turns on or charges. One group of cells were as low as 3.3, im not sure if the bms just shut down to protect the cells or it shorted. Now im charging the group of cells to see if it will turn on. Any other ideas to trouble shoot?