Attitude control with a Flight Task

I am trying to control a quadcopter (in SITL) in a GPS-denied environment through a Flight Task that sends only attitude setpoints. My goal is to send attitude setpoints directly to the attitude controller, bypassing the position, velocity, and acceleration controllers, as well as the “Attitude and yaw-to-attitude” block. I do not want to use offboard control and I still want to profit from the built-in PixHawk Attitude and Rate controllers.

I created a Flight Task that publishes values to the vehicle_attitude_setpoint uOrb topic. I attempted to integrate my Flight Task into Flight Modes that do not require GPS (such as Altitude Control, Stabilized Mode or Manual Mode), disabling the mc_position_control using the commander and switching to the mode that includes my Flight Task. However, the drone does not seem to respond to the published values.

I have two questions:

1) Is it possible to control the drone by sending attitude setpoints directly with a Flight Task through mc_attitude_control?

2) Is my approach correct, or am I making a mistake somewhere? (I’m relatively new to PixHawk development.)

I hope my explanation is clear. If not, I can provide further details.
Any help or guidance would be greatly appreciated!!!