My immediate guess is that someone pulled them out of there with summoning magic. That way they don't need to know exactly where they are and can bypass the cloister completely.

However, that might make sense for V - the rest of the order might have run into someone with that kind of power (eg. V's master) since they are near an old elven fort. However, unless they specifically scried them out it wouldn't explain O-Chul being grabbed.

I'm not sure how summoning spells work though.