Was he, or was he not, armed and trespassing?
Yes, he was both. Be kind of hard to claim self-defense when you are both of those.
He also said he got down out of the deer stand and was leaving when he was shot at.
Doesn't seem like he was commiting any trespass up to that point. After all, anybody can make a mistake when it comes to knowing where the property line is. Remember, we have different game laws than you down in Louisiana. You can't just go bagging passersby who knock at your door. There must be a reason.
Eventually we will know more. My first guess was somebody in the hunting party took a pot shot at him which touched off a pretty serious gunbattle. He was the better shot.