First, you need to test the switches.
do they pass 9 volts ? that would put them on the high side.
do they then go into a voltage divider and pass 5 volts to your circuit ?
if you change one while the unit is running, does the switch do anything? or do you have to have a power re-set ?
reverse hacking requires some careful inspections and testing. testing for both operation as well as the physical aspects.