Okay! So hermione's compasses do track names and the like, so you can get proof of Wan's traitorous ways (and his name) if you can track down which device he messaged directly. Or that it came through on Hermione's network at all. Idk how easy that will be found out. Wan will be getting through to the one Seelie he trusts the most, but again, that's down to actual IC investigation.

Also! Apparently, there will be at least one other who will be giving a warning. So it might not even be Wan that's tracked down. ¯\_(ツ)_/¯ But that's what I can give you! :)