What kind of predator might eat everything except some skin and the head of it's prey?

The past couple days have been odd. Today I was riding a horse in our field and noticed a skull. At first I thought it was a white tail deer, because we have a lot and it was the right size, but when I got off to look, I suddenly thought maybe it was a coyote, because the fur still on it reminded me of gray dog fur but more shaggy and "wild" looking then a dog. Talking to my father, I learned that yesterday he found a "body" missing a head. I looked at the body remains, just skin, and the pelt was a red-brown with white on what I would guess was the tail--a fox. However, the head I found was the size of my foot (8 1/2 women's) and grey, and really didn't seem like it went with that. Then, after finding the head, I walked to where the body was found (they were a couple acres apart) and found the remains of what I believe was a raccoon based on the small patch of hide left attached to the small skull (but it also had white whiskers, like a possum, though the fur didn't look possum-like). My dad says the 'racoon' was not there when he found the fox pelt yesterday. Other facts in this weird going-on are that the fox body had hoofprints imprinted on it. We have horses in our field so it is possible they a) killed whatever it was b) stomped on it after it was already dead because the smell scared them or c) just accidentally trampled it walking through the woods. Another thing is, both the fox pelt and raccoon remains were found next to/near a pair of large holes in the ground that I know in the past groundhogs lived in. The next piece of the puzzle is, when I showed a not-great quality photo of the 'coyote' head to my mom, she thought it looked like a sheep's head. To me, the fur didn't look right, but after googling pictures of sheep skulls and coyote skulls, I was wondering if maybe the teeth were more like sheep (I didn't notice any fangs like a coyote skull has, but is it possible they'd have fallen out)? The last thing is, I live in rural Maryland. I'm about an hour from DC, and 30 mins from other smaller towns though, so while it is farm country it isn't "wilderness" or isolated, although on the other hand we do have a good bit of woods and a small "mountain" (hill really) with some 3-5 mile hiking trails. Basically, this is not cougar or bear country, although we have had the occasional one wander through (same with bobcats). Foxes have been the top predator (ha ha) until in the last couple years some coyotes have shown up, though they are rarely spotted or cause any problems. I am just asking folks on here because I am curious about this weird occurrence (we've lived here about 20 years) and wondering if anyone knows what predator, or combination of predators might be doing this. The one other idea someone here had is that something is killing things to eat and we have some scavengers on the property (skunks?) dragging the remains back here, although even in that case I'd still like to know the species of each.