A question about my Witch Blood and Game of Thrones' "The Watchers on the Wall"

Without being spoilery here, at the end of the most recent Game of Thrones, I realized that, in very broad strokes, George and I did something similar: a small group of people are trapped in a fortress against an overwhelming force, and one person decides he must solve the problem on his own.

Now, I'm not saying George got the idea from me. I have no idea if he read Witch Blood, and if he did,