What do the hunters discover while they are out looking for the beast? what does jack think of this?

I can't answer this question. Be a little more specific with your wording please.

Ok, so when the hunters are supposedly find a monster/beast they found something much darker. They actually found a body of a military pilot who had ejected from his plane. The hunters then decided to keep on searching for the monster, but instead, kill a sow, in a violent, ritualistic manner.
Hope this helps :)
(Sowry that I only could answer the 1st part of your question)
Cheers, Irys :)

It has to be probably c