I'm gonna throw another bit of (semantic) evidence into the ring for Moe being behind the Cish attack. The scene is Kell and Moe in the interrogation room, discussing Moe's apparent lack of strength in the Water (TTT, US version, hard cover, 2006, pg. 350):
"I have some facility for those elements of the Psukhe that require more subtlety than power. Scrying, Calling, Translating..."
To me, he basically describes all the necessary disciplines of executing the attack on the SS. Scrying to see where he needs to send his assassins. Calling, as we know, was the base principle used by Kel to augment the gnostic cant of calling into a meta-cant of transposing (i.e., teleportation). And Translating... to me, the ace in the hole. While the most common definition of translation is from one language to another, I don't think a blind Moe would be sitting around creating Rosetta Stones somehow. Another definition, according to Google anyway, is:
"the process of moving something from one place to another"
That pretty much seals it for me, along with the already-mentioned motivations about arming the Holy War with a School powerful enough to overcome the Cishaurim, and the whole kicking the skull in the dark (i.e., Kel makes a mistake in his assumptions), etc. To add to the School comment, I believe Moe was aware of the Mandate and their power. With the destruction of the Cishaurim, the Scarlet Spires was also broken. They lost so many sorcerers of rank that they could no longer call themselves the dominant School of the Three Seas. That honor went to the Mandate, and Kel became their most powerful practitioner. Moe handed the Mandate to Kel, effectively.
As for the Consult being behind the attack... I never got that impression at all. If it's there, I don't see it. They could have simply instructed Chepheramunni (the skin-spy) to kill the Grandmaster, and the SS would probably have come to the same conclusion: that it showed no bruise of sorcery so it must have been Cishaurim. Doesn't make sense to me.
