It isn't that important for my theory, because this rather deals with the question who hired Slayer, if he was the direct killer of Asmo. Not directly with the identity of the one who actually did it, though one could call it an indirect clue in LoC, as RJ does.



Yes, I think so. Surprise, opportunity & timing are the keys to manage it.



Slayer offered, though, to try killing Rand again, though it was very possible that Rand isn't in Far Madding anymore.



Asmo lost his Chosen status at the end of TSR. And if a real Chosen orders Slayer to kill the betrayer, he naturally would. Besides, the Forsaken are naturally arrogant, they usually don't even have much respect for each other.



If it was as simply as you and the others think, RJ wouldn't need to write an extensive note about the murder with all details and what lead to it, and certainly more people had sent/told RJ the right answer.

The idea that Graendal did it is in my eyes a typical bandwagon effect. Although not much indicates that Graendal is the killer before LoC, people just accept it as the obvious answer, because it seems comfortable. But if one actually looks at the mystery, Graendal simply doesn't make much sense.

That said, I still think that Graendal is the best suspect after Slayer, because the other candidates fit even less than Graendal.