I have read all the books, all the Dunk and Egg stories, own both Seasons of Game of Thrones, spent way to much time on Westeros.org, and own the map book.
Jon definitely will pull through his situation. He has Ghost and a Red Priestess. He also has a lot of Wildling and Nights Watch friends that should come to his aid immediately. After being backstabbed by his brothers and possibly 'dying', Jon probably won't be a Crow anymore.
Stannis should survive his battle in Winds of Winter. The Manderly's are going to to turn on Ramsay and the Freys as soon as the battle is about to begin.