At least, that's what I'd like to see happen. I know there are a lot more exciting ways for her to die, but I'd like to see at least one Forsaken brought to justice through "conventional" means - i.e. similar to what would have happened to her, presumably, had she been caught during the AoL.

I don't remember which book it was in, but it was mentioned somewhere that that is how the WT would deal with one of the Forsaken if they ever caught one.

As for how she could be captured ... maybe she gets knocked unconscious during the Seanchan attack, and shortly thereafter Alviarin identifies her (deliberately or perhaps inadvertantly) while other (non-black) AS are within earshot.