Curious where you saw the end zones were 9.5? I agree with most of your assessment. I was in the Purdue section, basically right behind the goal post. Great seats for a baseball game, but we were effectively too low to see much of anything on the opposite side of the field. And most of the action was on that side of course, including all 3 touchdowns.
Interestingly, you pointed out that NW entered from center field. Their initial entrance to the field for pregame warm-ups was out of the stands right behind the goalpost. We had just walked in, a little early, and were just checking out the scene and suddenly the NW team was coming through the seating aisle one over from where we were standing. Maybe that was just a special way for them to come through their family section, I don't know.
It's certainly not ideal for a football game from several aspects, but it was definitely entertaining and a new, fun experience.