When the auction is over, the seller has a binding contract to sell to you. That's what ebay always says. Unfortunately, you can only dispute it with ebay and she will be suspended only if she does this so many times, not just once.

As for the excuse that she didn't know. I wish I had a nickel for every time I hear that on a daily basis from my high schoolers. I always say "So, if you don't know the speed limit, you can go as fast as you want?" If she is being honest and didn't know, then she didn't read the rules and she still is obligated to abide by those rules. Being ignorant is no excuse.

You've done what you can. I wonder if that website ebayersthatsuck.com is still in existence??????