She wants to "capture" all of the marath'damane there and "capture" the White Tower. She wants to collar all of them and use them to win the Last Battle. Not kill them, and not level the WT. (They're entering through the basement, not destroying the thing). Her last sentence is that the WT is doomed, which may sound like an indication that she wants to demolish it, but that's obviously meant to mean as an institution because of her thoughts 4 paragraphs prior when she says the opposite.


Anyhow, I find it very likely that they'll arrive at the WT and it will be empty or Mat will be there fetching the Horn.