The two animals do look similar and I can easily see how they could be mistaken, especially from a distance. These hunters were lawfully at hunt. These folks showed up, with dogs off leash. This is a 6 in half, one dozen in the other scenario. Stay out of areas where folks are actively hunting. Conversely, confirm your shot before you pull the trigger. In this case, in that area, coyotes are present. The hunter believed he had a coyote.

I completely fault the hunter if the dog was indeed wearing a blaze collar, but the owners claim it was wearing a "colored" collar. That could be any color, which isn't blaze.

When you are outdoors during hunting season, especially in public lands where active hunting takes place. Wear blaze orange, and if you have a dog put a blaze collar or vest on it as well.