If Jon Snow is given stealth, does his ability actually trigger the Stealth? I'm not convinced because of the distinction between declaring and participating. Here are the necessary rules:
Jon's ability says he is "...considered to be participating ..."
Stealth says "...for each character [the player] declares as an attacker..."
The rules for participating make it clear that if you declare, you are participating. But I'm not sure it goes both ways. What do you all think?