Seems to me the son is certain he has authorization to let people on the land. No surprise here, This is common in family owned farms, mine included. While my name/spouse is on the deed, if my mother/father/brother/sister/son/daughter/etc., say you can come out and place some GameCams, hunt, fish or take pictures of wildlife, etc., then you can.
GREAT!!!! Where are you located? I just happen to be on the lookout for a new location to hunt. lol