[Spirator]

1/16 in. plate is very thin. You may want to consider beefing it up or consider switching to steel.

Also, like the other posts say, consider face mounting the VersaPlanetary instead of using the churro mount. That way you'll spread the load on the face of the motor and eliminate the bending moment and shear stresses on the churros and the aluminium plate.

The torque imparted by the winch on the gearbox is causing the mount to break.