When you have a very large building you wind up having a reduced ratio of surface area to volume. The thermal energy inside the mall has a harder time finding a way out than it would in a smaller building because there's just less building surface in comparison. It takes time to get truly cold.

I'm not an engineer nor had any part in designing the MoA. I have no idea how its heated or not heated at night.

Seems like you have a real axe to grind there.