the paradox is because the prisoner would know the hangman will come at noon on friday if he is alive thursday afternoon he wouldn't be surprised if he did come. then he concludes that it can't come friday because he would predict it and be not surprised. but since the judge knows he will say it can't happen on friday he will actually be surprised if the hangman does come on friday
what if it lands on its edge like in batman
the issue i see here is it is only a paradox if it requires the judge tells the truth and is always correct. but if that is the case then the prisoner is concluding that the judge is lying or made a mistake when he concludes he will not be hanged. so since the conclusion he won't be hanged is a contradiction itself how can he conclude it is definitely true? if he can't conclude his conclusion is definitely true then he will be uncertain each day