that sounds like a great place to put a trail camera... If you had wolves, I would suspect this might be a rookery site where pups are raised and kills are dragged back to the area for feeding. Mountain lions do hide their kills also, but I was not aware they returned them to the same spot (from what I have read). Also because of the size of the deer, coyotes could do it if they brought them back in pieces.

If you ever get back around there look for hair on branches and such. But that really is interesting. I think I would mention this area to your local game wardens and see what they suggest.