I agree with everyone else - the sgteard or other Carnival employees would be the first ones blamed so they have no ability to open the safes. It's just a matter of bad timing, that this just happened to have happened while you were on the ship.
Of course Carnival could find out who the itemspurchased in the Phillipines were shipped to - if it was friends or family of the steward, that would certainlpy pint to him as the thief.
Don't blame until you have proof.