honestly by that point there wasn't that much left of interest to me in regards to the Forsaken. Not sure what would have qualified as a "bombshell" either.

Here's who was still around by that point:

Demandred/Boa: Killed by Lan
Graendal/Hessalam Bounceback compelled fighting Aviendha (can't remember if she died or was just essentially a mindless slave at the end)
Lanfear/Cyndane: Killed by Perrin
Moghedien: now a good damane
Moridin/Ishamael: Body swapped with Rand
Taim/M'Hael: Killed by Egwene

Dead before AMOL:

Aginor/Osan'gar: Killed by Elza
Asmodean: Killed by Graendal
Balthamel/Aran'gar: Balefired by Rand
Be'lal: Balefired by Moiraine
Mesaana: Mind destroyed by Egwene
Rhavin: Balefired by Rand
Sammael: Killed by Mashadar
Semirhage: Balefired by Rand

Given that it sounds like there was very little fan-theory around this I'm inclined to think it doesn't involve Demandred since he was the subject of a million theories and a novella. But then, Sanderson also seemed to be more deeply involved with this character than the others so perhaps he's more in tune with that?

Lanfear, aside from the Cyndane discussions and her drop in power, seems relatively unexplored theory territory, so perhaps we missed something there?