I don't know, but Venli can tell that Leshwi is coming down the tower before she gets there
By the description I got the impression that it was set to ignore each person specifically, but it could be people already in range.
The Codes of War specifically say to never be drunk and to always have a weapon. Nothing about armor.
Sorry, that's a big as it will let me make it.
One, who cannot impersonate singers or radiants, thus limiting the number of people they can accurately mimic. And they have been on Roshar, not necessarily are there now.
New plan, take Nightblood into the CR, go to large important cities and start stabbing buildings, factories, important people etc, until Scadrial surrenders.