I finally got to the end (with help from your clue but without looking at the pdf). It's a really great looking game and fun to play.
A few comments - it wasn't clear what Clark Kent was pointing at when he says 'you haven't been in there' (the alley or the cleaning supplies room), Wilt can confuse things if you have already looked around before he appears (he tells you what you have already found but you think there is now more), on one occasion the kids were not moving when I entered the alley.
Thanks for sharing this excellent game.