Wasn't that line (the one saying that the hangman comes for him on wednesday) just supposed to be an example? I didn't think that the problem required the hangman to come on wednesday; I thought that it left open when he would actually come.
(And, no, I'm definitely not making fun of you.)
Oh, I see.
At first, I missed the significance of this passage:
The warden's statement is then false and unparadoxical. This is similar to the one-day analogue, where the warden says "You will be executed tomorrow at noon, and will be surprised" and the prisoner says "wtf?".
Then here's an analogous "paradox":
So, yeah, that's why I said that it sounds like a garden variety contradiction.
Good point.