Hi Matt,
I've seen this happen before - you start trying to chase each air molecule along its path and figure out where it's going to go next... it's easy to get down in the weeds since the development of airfoil shapes is such a deep deep subject. There's a lot to read about the subject, but it's not often prioritized in a way that helps keep perspective.
Instead, ask a simple question from personal experience - what makes it possible to gently throw a frisbee, a playing card, a bowler hat, a boomerang, or a paper airplane and hit the far wall of the room?
Surely the shape isn't the biggest factor because a boomerang doesn't look anything like a hat.
Your shape looks like the cross-section of a paper plate, and I'm sure a paper plate can fly across a gymnasium and hit the far wall if you wanted it to.
Anchoring what you learn with the facts you know and that make sense in personal experience helps prevent misunderstanding and confusion. That way you can avoid being misled by stuff like "Reflex curves self trim, which means it would resist blade twist." which isn't true, doesn't make sense in a wind turbine context, and hints that you're reading stuff from airplane model builders who may be confused too.
You're definitely right, that fowler flaps have no place in wind turbines, just like slat's don't either.
Here's another avenue to investigate, hopefully that will help focus attention on what's most important: where is the flow attachment point on the leading edge? If the LE is round, the attachment point can change as the angle of attack changes. If the LE is sharp, there's only 1 spot for it to attach to. Look at the profile you proposed again, with this in mind - it's the second case. What are the implications of that? How would it behave at negative angle of attack? At high positive angle of attack? Would the same conclusions apply to a WT blade made from a plate of steel?