What if the body was in a hazard? Does that change the ruling?
If the ball is laying on the ground, then you obviously can't ground your club in the hazard. But if the ball is laying on the body, I don't see why you couldn't ground the club on the body, as long as you don't touch the ground with the club.
If the lie of the ball is in such a position that the body is in the way of getting a proper stance, I don't think that you can move it if it's in a hazard. I'm not sure on that one. To be safe, I would just stand on top of the body, assuming I had the old metal spikes on and could get good traction.
Then, I would tell someone in the clubhouse at the turn, obviously, to try to get the poor fellow some medical attention, help and/or the coroner.
Hope this helps for the next time you are faced with this.