Using vesc for Position and driving my BB8 Robot

Hi everyone, i come across this esc due to seeing youtube videos explaining position , i am working on a BB8 project and looking for a controller for the head

control, which is using brushless motors this esc would be perfect, i would have to redesign the PCB to have two controllers to save space and the main drive to have a forward and reverse driver

my questions are, i would like to use harmonic drives and encoders, i have  RLS RM08 12bit  encoder with SSi interface which works by bit banning the clock and reading the 12bit of data that is

the position of the magnet and the output is the current magnet position and will always give the  value of where the magnet  even if the power is removed

and returning an integer can this be added to the firmware, also can the encoder be put on the output shaft of the gearbox and not the motor

the other is do any of you already have the already setup code for using the cam bus or SPI slave to set the position and take out anything code that is not really need