Either the Coyote was rabid or his story is bunk.I can see the coyote attacking the dog but coyotes don't attack people unless their rabid or a person jumps into a dog fight or it's a baby or toddler might be a possibility. I"ve wandered into coyotes numerous times and they either immediately run or they stand still and watch me till I start to approach them and then they get out of Dodge.We are badder then they are and they recognize this. They have learned through the school of Hard knocks that we are bad news. If a coyote walks up to you and bites you, you need some serious shots at that point.