Aha -- Bernoulli strikes again!! Interesting theory, & plausible as well.

However, this is where we part company. Go back to the torque rings and think about what you are seeing. You are looking at the "track" that the prop tips are following as the prop advances through the air (it doesn't matter if the plane is stationary, the props are still advancing through the air). Keep in mind that they are driving the slipstream, rather than being driven by it. What you are seeing is an interconnected series of loci showing where the prop tip was a few moments previously. You see exactly what you should see in a prop turning clockwise. The slipstream is indeed swirling from left to right, as the prop tip is moving from left to right.

In the case of the (relatively) absent roll in the high AOA approach to a power on stall, you are now faced with the contention surrounding fluid dynamics vs Newtonian physics in explaining the effects of the swirling slipstream on the wings of the aircraft.

Your theory is dependent upon conventional fluid dynamics, as represented by Bernoulli's equation. If you view it through Newtonian physics, a different picture could emerge, at least in certain circumstances. Think of the slipstream swirling from left to right (it can't go in any other direction) & visualize it impacting the flat underside of the inboard left wing -- action & reaction. At the same time, visualize it impacting the curved upper surface of the inboard right wing -- again action & reaction -- but less reaction force as the air spills more easily off the curved surface.

This represents a moderate right-roll force that counters the left roll torque reaction force, which combines with the roll resistant normal lifting forces in the outer wing pannels -- ergo no roll untill stall, wherein the total loss of conventional lift permits the torque forces to overcome the weaker spiral slipstream effects.