Think about it .... no football weighs 13 pounds. If it did they would have to throw it like a shot put.
Well, that explains Cam Newton....................
Yes, it would be like trying to pass a football-shaped bowling ball..
I don't know what the temperature was when and where they inflated the balls, vs the temperature on the field at game-time, but if the balls were inflated at room temperature and then cooled down on the field, the psi would drop. That, however, would be the same for both teams. If the balls were different psi for each team, I can't think many reasonable explanations for how that could happen without cheating.
If the NFL does not inflate and check the psi of their game balls under the conditions of play, that is a problem with the NFL not being careful enough - not a problem with the team. Interestingly, if you wanted to cheat like this, all you would have to do is warm the game balls before the opposing team used them (increasing the psi), and cool them down before you use them (decreasing the psi). This could be done with on-field ball warmers set to different temperatures.
Interestingly, if one had ball warmers set to different temperatures for the home team vs the visiting team, one could vary the psi during the game, and after the game - under identical measurement conditions (e.g both balls at room temperature) there would be no differences noted. So, it's a relatively easy way to ‘cheat’ without being caught.