Unfortunately water in the underground gas tanks isn't all that uncommon after heavy rains. I don't know how it gets in there but it happened at a few stations in the Indy area earlier this year. I do know that the stations' insurance did cover damages--so have faith in Carlos! I'm sure you are NOT the only person who experienced this at that station, so numbers will be on your side.
I hope it all works out and that they can fix your car!