So, if you have the minimum number of city defenders for your population and one of those defenders dies in battle, the team is instantly disqualified, even if another defender can take its place same turn?
I don't understand... You dont take defensive battles during your turn. Number of defenders only applies to YOUR turn, when you settle or conquer a city. You can move your units whenever and wherever you like, just be sure you have enough in your capitol when you settle (units can even partially move to capitol in the turn you settle, take screenshot and you can freely move units out of the city if they still have enough movement points).