So Nova responded to me saying I was correct in that my ability should work passively, and that it'll happen when there are "eligible" dead players. I've asked why Muugen and Adam are not eligible, and am waiting a response.
I've confirmed that it bypasses whistle links, so as long as I'm in the game every player not janitored should be able to post in the chat, it's more like a separate thread actually. My understanding is that if someone reveals the identity of a janitored player with an ability, they would then be "eligible" to join my chat.