Those inboard slats never fully retract. They seem to be built for some motion, but it's obvious by looking at the FS one that they never actually retract flush

The reason that these are important to have near the fuse, is that the engines are directly behind the wings - which you all knew - and they draw alot of air. It is vital to maintain a smooth flow of air into the engines, especially when yanking a high-alpha maneuver. Same reason there is such a big root fillet on that wing. So, the slats are there more for the engines than the wing...... huh? Yeah, they keep the engines from eating a bunch of dirty air when the wing would have otherwise been causing alot of problems with airflow to the engines.

I will be building a big A-10 over the next few years, and I will put them on - fixed in place.