Puns NEVER need forgiving! :D
I get what you mean about puzzles. They can actually be pretty fun destroying if too hard. I've only been making visual novels for a year but I remember reading somewhere in my travels that the demographic is less likely to want puzzles in their media so I've tried to find a good balance between simple and rewarding. And yeah, in game solutions are a must I think :D AND oh yeah, Zero Escape... so much maths! WHY!
And absolutely no need to apologise, you are not terrible, the puzzle was WAY too obscure. I have no idea why I thought anyone would get it. The playtester in question is actually a huge Michael Jackson fan and especially loves Thriller. So when he didn't get it, I knew I was in trouble :D