I would bet that the Bison have spent a portion of every practice this year working on the game plan for Iowa. Sure, they had two tough games before the Hawks, but they knew which game was more important nationally. They could use a part of a few practices to game plan for Charleston Southern and Eastern Washington, but they had to believe they would still win or be competitive regardless. They also have a bye coming up this week. This was their Super Bowl, and their preparedness for Iowa showed in the game.
The Hawks, OTOH, looked at it as just another game, and one they should win. Big mistake.