DRV8305-Q1EVM: can customer remove the BEMF sensing circuits?

Customer would like to use similar design as DRV8305-Q1EVM did for their water pump design, with sensorless control scheme. They wanted to remove BEMF sensing circuits. However, if so, DRV8305-Q1EVM could not work as expected. 

Could you please help comment whether they can remove those circuits in their own design? If so, what changes are required in the present firmware using F28027F? And they planned to use F28035 for the controller instead, but we found the present firmware used InstaSPIN-FOC on the TMS320F28027F,so how can F28035 use the same algorithm in the software?