The first question I need to ask is? What was the reaction of the deer when he shot it. Did it just run off with it's tail up high, did it buck and kick out it's hind legs, and tail held down. Was there any hair on the ground where the deer was hit. Following up on a deer trail that doesn't show no signs of blood or hair. Tells me he missed. There has to be some kind of sign where the animal was hit, and also where she ran off before she ran into the bog. How far into the bog did you go?