It appears to be the hand of a black man.
Also, if you look at the area from the wrist down, you'll see the sleeve sticks out.
As I said, the shoulder down looks like a straight cut and then at the bottom it appears to stick out at the wrist.
In any event, the skin tone of the hand (which looks like the skin tone of a black man), even accounting for the shadow, is dramatically different from the skin tone of Podestas' face.