JRam,
That burned one is the Battery current shunt amplifier but the PV shunt amplifier that looks similar also seems to be damaged or at least the 1.3KOhm resistor has a burned mark meaning likely the microcontroller was also damaged.
Your installation was sure incorrectly made and in more ways than one.
First of there should be nothing between the current shunt and battery+ so no fuses, breakers or switches.
What have you used as a charge source as you do not have a DSSR20 ?
The battery current shunt is the LMP8481MM-T (bidirectional 20x amplification (denoted by that T at the end) ) and the PV current shunt is MAX4080TAUA+T (unidirectional bust still the 20x variant so is important to have that T in the part number as there are different ones with other amplification numbers).
But I'm sure the STM32F373 microcontroller is also damaged even if it looks like it may still work some parts of it will be damaged for sure based on how that 1.3kOhm resistor looks like.
Not sure what you mean by a cell spiking up but is fairly likely the charger was not controlled by the SBMS0 and SBMS0 needs to have ON/OFF control over all charge sources and separately over all loads.
More details about your configuration will be needed to know what was not correctly setup (likely more than one thing).