he was in freefall for 20ish seconds while the plane was seemingly flying away from him straight and level at ~70 mph losing altitude at a moderate pace. So at the time he popped his chute he was several thousand feet below a plane that was last seen flying away from him. A parachute has a higher sink rate than that plane as well.

Somehow the plane then ends up losing altitude VERY quickly before leveling off again, and by chance circling back directly underneath the pilot in the process. It could theoretically happen, but also seems ridiculous when you put it in context.