well I too don't think coyote's will group up enough tp bring down 5 deer that close to each other, and keep them there and kill all of them
thats a pretty big task
and if you had that many coyote in your area you would be finding a ton of dead der all over, and fwe live one's on your lands
NOT saying its impossible, just to me not likely
that being said
IF I had to guess , I would almost say maybe someone poisoned them, lots of folks hate deer, and its not terrible uncommon to have a person feed them something bad
and that can even happen to folksd meaning good
corn can go bad, and actually kill a deer if they eat enough of moldy corn off a bait pile
and well, in winter deer do yard up(also a reason making a coyote kill being lower odds, they tard up for protection!)
so to me , I say thats a higher odds deal, they all ate together, maybe a family group, and all ate the bad food, and thus??
NOW EHD or something else is possible too, but normally again you find a lot more dead deer in the area
IF your good with your state game dept, you can call them and ask them, they might be able to test the remains?
or might even know of a neighbor that has a MAjor issue with deer/crop damage, and a dis ike of deer
odds are these folks have complained to the state many times before acting out!
that's my guess/suggestions
and sorry,
it sucks I am sure