If you have some email supporting your case, you may have something. If not, it's your word against his - and that "ain't gonna fly".
Regardless, given that you want this to remain hypothetical, I would suggest buying a voodoo doll and lots of pins - but nothing else. It's not worth the bad energy...
Safe flights, Sam.
PS be happy that he's going to have to spend a lot more money getting his plane now!