Were the two guys in cowboy hats included before you knew it was Stampede w/e?
Yep.
What's the back story with them on the poster?
Backstory? There's no back story.
Everything else in the poster, besides the woman with her fist in her mouth and Jay Wright, seem to have KSU significance. I'd never seen that image before, or the woman, so I figure it has some significance to be included in the poster. That's all I was asking (now I'm curious about the woman as well).