Clear? The vulnerable token is also declared and used "AFTER DEFENSE DICE ARE ROLLED". That is why I posted here since it is not clear.
On top of that "If either player has effects that would cause defense dice to be re-rolled (like shields and vulnerable token), they are applied now". This part sounds like it is done at exact same moment. That is why I really hope for a clear answer from CMON staff.
Blackjack006 clipped the exact section that matters from the rulebook. That second bullet point is what you want. It sets the timing for declaration and resolution. Active player both declares and resolves their re-roll effect first, followed by the inactive player. This makes it a bit more complicated than you might think. Let's take your example from above. You attack into a Night's Watch unit with a Vulnerable token on your turn. After the NW unit rolls defense dice, you make the declaration of spending the Vulnerable token if you wish. If you do, the NW player re-rolls the dice you choose, as the rulebook says you both declare and resolve the re-roll effect of the active player first. Then, after seeing the result of the Vulnerable re-roll, the NW player then has the option to declare and resolve The Shield of the Realms of Men. If they do, they re-roll their chosen dice.
Now, the complicating factor is if it is actually the NW player's turn. There are effects in the game where you might be attacking during your opponent's activation. This still makes them the active player. So let's say your opponent has a Vulnerable NW unit and they attack you, a Baratheon player, while you have a unit of Baratheon Sentinels within charge distance. The NW attack is done, so you spend the Sentinel order to get a charge on that Vulnerable NW unit. You attack, they roll defense dice, but now the NW player is still the active player so they have to declare The Shield of the Realm of Men and resolve their re-roll first, then you may choose to spend Vulnerable after seeing that result.
Now, that is the rules as written for re-rolls. They're very specifically called out for how those effects work. I understand you were looking for an answer from CMON staff, but they haven't answered anything here in the rules forum in months. If you are waiting on CMON staff, you could be waiting quite a long time to get your answer. My recommendation is you and your group decide what answer you've received that makes the most sense to you given the rules in the rulebook and play that way. If you intend on going to a tournament, contact the tournament organizer and get their ruling. Don't try to argue/plead the case, just run your tournament prep games however the person running the event is going to rule the interaction. I recommend this for a lot of uncertain rule interactions, actually. If your preparations are for local events only, then ask whoever your local organizer is going to be for their ruling.
