The uppers on shoes, are made of chrome tanned leather, or something very similar. In that process the cells are filled with something, and the result is that the leather is not free to soak up liquids for the most part. So there is some chance the penetration is entirely superficial. Only to suggest that the damage may be only skin deep. Therefore maybe it can be repaired by experimenting with some of the suggestions.
Of course chrome tanned leather is not vinyl. Stand around in water and they get wet, but they do not respond like veg tan, and the test to tell the two apart where not obvious is to see how they soak up some water on the surface.