I've PMed Graven once again, but since he hasn't replied or seen my previous PMs either, someone should email him - as administrators, we have access to his PM right? I like your idea of him falling comatose, if he will not post in the next 72 hours - this is a good failsafe for us (I can roleplay this on the next turn, on Katherine's POV). Also, because I imagine Graven will say (if we NPC him) that he is not going to just give up, Katherine will likely sentence all Espada and their shinigami allies to death and her roses are going to disperse to kill whoever is left standing. In addition, Cassandra (the venomous snake rose) can induce the comatose state with her practically-omnipotent poisons, that she can practically manifest from any part of her body.
Katherine is going to try and execute Dante on Karasu's castle. My guess is, Seach walks in, and Katherine and he have a convo about the sides of the war to follow - Dante SOMEHOW manages to escape them both, maybe helped by another deus ex machina and goes into hiding. The Army of Blood is now without it's leader and tries to hold onto to the lands of the West and the Heart of Darkness. Espada is broken by the state of their leader, and forced to retreat with heavy losses. Katherine takes Annora, Alyss and Morgoth as prisoners, leaves Graven for dead and goes back to the East to prepare for a three-way war with Seach and Espada.
Personally, I think we should keep Graven as the Primera for a while, as long as he's alive. If Graven falls inactive, his character becomes a staff NPC (WHY ISN'T THAT FUCKING RULE IN PLACE ALREADY). We should keep the organization top dogs as NPCs, and put an OC in an org leader position only after we have more members and support for these OCs to take such roles in-character. Graven is the founder of the organization and throwing him away just because he fell into coma doesn't seem right - the Espada would wait and wait, until all hope is lost. In addition, the furies might or might not survive the battle, depending on how it goes - also, I don't see Kuroi persuading them to join them, but of course, this depends on how the thread continues. Lambda thinks Kuroi is a fool, while the other three are irreparably broken and lost without Dante. Kuroi should remain as the Segunda, but he could be de facto leader of the organization. Not all would bow to him, of course.
This is my few cents-