RE: What now?
FRIAR, what is the terrain like in the area you are hunting. It is quite possible the hogs are living somewhere else and only visiting this place at night. We run into this a lot hunting with dogs. Go into an area that is literally ruined by hogs and end up finding them 2 properties over because that is where they stay during the day. Go back to the same spot at night and hogs everywhere. Sounds like this is what you may be dealing with. Walk the whole property if this is feasible. You find the bedding area you will know it because you will smell it long before you see it. Look in the thickest, nastiest place on the property. If you can find where they are staying during the day hunt close to their at sunrise or sunset. Are feeders legal in OK? Great way to trick the piggies.