I'm perfectly content with him still being the bad guy. A Shard waging war on the Cosmere? That's more than enough bad guy for me. It also lets him keep bouncing the forces on Roshar off each other and skimming the cream off the top. As much as I loathe to reference it, Dune did something similar with the Sadaukar. I'd go so far as to say that that had also been Rayse's plan; he never seemed all that invested in the singers, so much as just wanting the conflict to persist.
This is going to sound very silly, but I did remember that WoB, just... Backwards. I remembered it backwards. Ope.
I mean, stuff still stands, I guess, just a little embarrassing on my part.