Look at towers of midnight, what one of the finn's says right after they take mat's eye.

 

Towers of Midnight, Chapter 54: The Light of the World

 

"How it twists around him!" said the one who had taken his eye. "How it spins! Scents of blood in the air! And the gambler becomes the center of all! I can taste fate itself!"

During the last battle, Mat was sure important but not necessarily the center of all. So it can go to reason that this will extend to after the last battle, and he will have to continue to be ta'veren. 

Two things: I think that the glass pillars were showing the possible future just because I feel there were a couple things in the visions that didn't quite add up to the present.

Second, even if the pillars were telling the truth, remember the fact that there are seven ages. Each age repeats with some slight variations. Even if the Seanchan do win out, eventually, they find there downfall. Take comfort in that.