My own thoughts:

1. Demandred is a Seanchan general. I arrived at this unscientific conclusion based on the fact that he, Mesaana and Semirhage had a plot together, according to Graendal. Semirhage used to be in Seanchan, Mesaana was in the Tower. Despite Semirhage having been captured and balefired, the Black Ajah STILL knew of the HIGHLY SECRET Seanchan raid ahead of time and managed to escape. This points to Mesaana's surviving co-conspirator, Demandred, being in Seanchan. Furthermore, Demandred claimed to have an army (and liked commanding them), but Graendal (discounting the Seanchan for some reason) couldn't think of any armies big enough left in the world other than the Borderlanders.

It fits that he is commanding armies of Seanchan.

2. Asmodean was killed by Lanfear. She might not even have been Cyndane yet when she did it. She had just fallen into the realm of the Eelfinn and was granted three wishes if she agreed to pay the price. She probably agreed, with one of the wishes being to kill Asmodean, at which point she probably was given temporary access to Caemlyn to kill him.

That's not a new position, but I do agree that Graendal's POV seemed to indicate she hadn't really done much for the Shadow and if she had killed Asmodean, she would have thought about it.