Here is the spec sheet for the main square chip on that board.
http://www.ti.com/lit/ds/symlink/bq76pl536a-q1.pdf
You're right. It does have a cell balancing feature.
For cell #1, my guess is that the 4 parallel resistors (R3) are the balancing resistors and that Q1 is a small logic level MOSFET which enables cell balancing. On a BMS project I'm working on balancing current is only 250mA, so a small SOT-23 MOSFET is all you would need.