The house must have been damaged …so the water could get in the garage..
Houses are not watertight, especially garages. They fill up with water very fast.
The daughter of a neighbor and her husband live in Tampa. They bought a house that is built on stilts 10 feet in the air. Plus, they hang their belongings in the garage from the overhead joists. Nothing sits on the floor. They got a few inches of water but nothing was damaged. They also moved their cars to high ground.
I just heard a little while ago that the arriving tenants for their attached AirBnB decided to come even though the hurricane was about to hit. The tenants didn’t move their brand-new car to high ground a few blocks away and the car is now totaled.