Microsoft Surface book Charging controller card

Hello all,

My Surface Book keyboard has failed unexpectedly: battery is not recognised anymore, no charge through the keyboard power plug anymore , all the peripheral connection ports are dead , the power supply failed as well. The batteryreport utility software indicates an extinction of the batteries without prior serious decrease in capacity, the latest record shows a capacity of both batteries at above 90% of the design specs.

At present, only the tablet part works. The detachment button on the keyboard does not work anymore.

I disassembled the keyboard: The 4 cells making up battery 2 are in good shape and deliver a 3.55 V voltage each. All indications lead to a failure of the circuit board lying between the power plug, the battery cells and the connecter to the tablet part. But I cannot remove it yet because I don't have a screwdriver fitting the screws.

Any idea to repair it ?