Well, my old Canon Powershot G10 wasn't able to turn on, so I concluded it was dead. Then I grabbed my screwdriver and put it into pieces. I removed some parts such as a capacitor, microphone, speaker, LCD screen. Then I went on google and I searched it. I saw it was still pretty expensive. Did I just made a mistake? Should I sell the parts on ebay?
You shouldn't sell any parts. You can't now guarantee they will work as that dunking in the pool could have affected anything.
So on answer, I don't think you were stupid, the camera was most definitely dead prior to the disassembly, with no hope of fix by you, even a camera repair shop would advise the best option of a trip to the trash can