I thought maybe they had remodeled the Astrodome. I never went to the restrooms after the 2nd quarter of a football game or 5th inning of baseball for the very same reason when I used to take the kids there from Boerne. Sounds like things didn't change.
Last time I was at a football game there between the Oilers/Steelers, it was very hot in there and the a/c didn't seem to be working right.
This is a prescription for trouble.
Buildings like the Dome create their own weather systems. I have seen it actually drizzle inside when the A/C was out of balance with the humidity.