You want Interlude, Foes near and far, for that. And while Ostland is undergoing a Religious awakening, Malagor is nowhere NEAR Ostland right now. He's amassing power and troops in Drachenfels. Which means he's likely got his eyes on sights of more importance than that, doubly so given that both Middenland's countess and Reikland's count were pissed and paler than a ghost respectively after they visited the diviners. Malagor is likely to try and shatter Reikland and then move onto Middenland to destroy the original Flame of Ulric. I have no doubt the centigors will be hitting Ostland given we murdered their daddy, but it's not going to be the hammer blow, it's going to be the distraction to keep our forces, and possibly those of the Trident, out of play so Malagor can make his move. Because Malagor is able to make something akin to sensible tactics, and knows if the Empire collapses on him as one he'll likely get stopped short.
What I foresee is the Centigors rampaging into and out of the forest, hitting ANYTHING they can that's soft, and moving away, trying to get us to expose ourselves or our children by overextending to chase them down, then smashing down on us with their full force. Their conscripts will probably be used to try and hem in the new fire site of Ulric's too as bait. Their entire objective though will be two fold, keeping us from leaving, and causing as much pain and horror to our people as they can.