Really creepy woods , what happened to my happy memories?

Red neck hunters do that sort of thing all the time, hunting where they aren't supposed to. This happens everywhere. It sounds like the cow recently died, because you say it had been only eaten from the inside. (Insects move the the mouth and first because they like the warmth and the tissue inside of those areas tastes really good to them I guess.) Anyway, I'd say that the cow was probably there for 1-2 days, because after 4 days out in the open like that, insects would almost be completely done with the corpse, leaving only bony remains. I have no idea what a cow would be doing out there though. Also, it seems other people in that neighborhood have been back there. (little kids get curious, hence why you found those toys.) It is weird that the tent you found was still there though. Maybe some crazy person is trying to live there? idk.