Control surfaces not locking in Multicopter Mode forTilt Wing

I am testing an x8 configuration tilt-wing VTOL with a custom mixer that combines an x8 multicopter and a VTOL AAER mixer.

In Multicopter mode, after setting the vehicle from fixed to multicopter mode, all the control surfaces still run. I have tried it with both VT_ELEV_MC_LOCK enabled and disabled, as well as setting VT_ARSP_BLEND to 0.

This is an issue because the motors are placed directly above the ailerons and elevators when in Multicopter mode meaning that roll in MC mode would generate an unwanted yaw on the vehicle itself.

Any help would be appreciated.