Ever tried pre-cooling the coolers with frozen water bottles the night before? That trick saved me when our fridge crapped out during a brunch rush. Two coolers plus some blocked off space and we rode it out fine.
Heard a guy on a podcast say he keeps a little window unit in his car trunk as a backup for situations like this. Sounds a bit crazy but honestly after reading your post I get it. Glad you made it through the rush.