I don't know why it didn't work - maybe try doing it again? Not having the game, I am not able to test the puzzle bypass for myself.
Elsewhere online I found this advice:
There is one cheat built into the game, though--if you find yourself frustrated with the black and white grid puzzle (otherwise known as the "nonogram," "Conceptis," or "Japanese tile puzzle,") you can give yourself a hint or even opt out of it completely by clicking in the upper right-hand corner. This causes a large section of the puzzle to be automatically filled in for you. Do it enough times in a row, and eventually only one tile will be left for you to put into place yourself.