See what I getting from this, and you obviously cannot confirm or deny it, these are my thoughts. The failed kill was on Poison by the looks of it.
That's what I got from Poison's post as well. She's seemingly bullet-proof? So the kill could have failed on her.
Town : Me, Fuji, Usopp and Flowa.
Scum : Light ofc
The rest 50 : 50 including you and except Host ofc, they're innocent.
2 of your town reads are dead though. So only Flower and yourself are town for you among the alive players?
Reading back, flower was starting to get votes and the suspicion around her was starting to increase. After which her reveal was made in the thread. It might indeed be a passive and something like if Touka gets 2 votes on her then she will be revealed. But if that's the case, why didn't that happen on day 1? Usopp and I voted Flower on Day 1. So she should have been revealed then. The only reason I can see why the reveal wasn't made on Day 1 is if it's an active ability that Flower triggered herself, or votes must be placed on flower at the same time for the passive to work.
All of this is assuming the reveal is real and not fake though.
I'm still not sure how the event was triggered. Unless it's because of one possibility - The event is triggered if 3 soul mates die or 3 partners die or both. That means Fuji might have been Poison's soulmate and Poison is Subaru. Queen Emilia lost her partner in a super kill and Mango lost his partner by suicide.
That would explain why it's called Bloody Valentine. All 3 lost their partners/soulmates.