Posting fraud wasn't the best of ideas. Who's to say there aren't people who work for Apple that do these kind of check. Trust me, there are companies that do. Secondly, water doesn't evaporate in a day or two. It will take week(s) in an enclosed device like a laptop. Thirdly, I would suspect there is some sort of thing Apple has hidden to test for liquid damage. Most cell phones have that little dot that changes colors if it gets wet.
Don't you feel any soft of guilt? To me, it seems like a pretty horrible thing to do what you did. Apple shouldn't pay for your negligence.
Edit:
Water damage will easily cost $100 to repair like a keyboard up to $800 for a new logic board. Usually, the laptop is better to replace than fix.