For all the custom MobiFlight commands listed in events.txt you have to add the prefix MobiFlight. to them.
Thus you should be sending MobiFlight.A32NX_OVHD_ELEC_BAT_1_PB_IS_AUTO instead of just A32NX_OVHD_ELEC_BAT_1_PB_IS_AUTO.
For all the custom MobiFlight commands listed in events.txt you have to add the prefix MobiFlight. to them.
Thus you should be sending MobiFlight.A32NX_OVHD_ELEC_BAT_1_PB_IS_AUTO instead of just A32NX_OVHD_ELEC_BAT_1_PB_IS_AUTO.