People in my livestream tonight were thinking that the White Walker at the end of the episode might’ve been Benjen Stark. Considering that D&D have changed quite a few things this season, I wouldn’t be surprised if they decided to scrap Coldhands as we know him in the books and use this leader of the White Walkers to move the story along. I mean, why else would he let Sam live?
EDIT: Going back through the books as well as the Forum of Ice and Fire, I see what you mean. I glossed over the differences between Wights and White Walkers. Oops lol. But for all we know, D&D could’ve changed the definition entirely to suit the show. *shrug* Just a bit of headcannon :-P