Podiatrist only. Have overpronation/flat feet, can the looseness of ankle loosen knees then hips causing hips 2 dislocate?

Quite a stretch. There is no question that overpronated/flat feet, in time, could have an effect on the ankles and knees as well as the hips. To say that the feet would be the proximal cause of hip dislocation might be a stretch.