Chapter 8: OCC
A brief rundown probably wouldn't hurt.
Also, just to check, as far as Zelpuz knows, the most likely explanation is that the Order captured Lasrane, maybe they had a call out at the hospitals to notify them if someone looking like that appeared. That way they would know about the meeting, right? Otherwise, i.e. without talking to Lasrane and/or scanning him, there is no way to know about it.