Would you expect those assets to be included in source code, though? Roosters are generally fully customizable and EA games vary little year to year, I wouldn't expect players to ever show up in source.
That depends on how data driven player appearance, animations and behaviors are. I would start with the AI code and see if there are any player specific exceptions (that is, hacks) in there to match a certain play style.
I know that joking is not appreciated on HN, but the mental image here is absolutely fantastic. I'm giving my rooster a gigantic beak and three legs.