RE: How long does a deer need to lay?
I would go at 6 like you planned. 10 hrs is plenty of time. For most gut shot deer 6hrs+ is fine, so you should be good there. You also said the coyotes were a problem there so it might be mostly gone if you wait til morning. I would say he's dead and you shouldnt have a problem finding him, but they are amazing animals so you never know. Good Luck finding him.