In Jotarou's defense, when he was pulling the girl, he probably felt a breast already and was doing the torso check to be sure.You know Jotaro, you could have removed the girl's hat before attempting a torso check.
As mentioned in the episode, the fake captain set up some bombs on the ship. The big question though was the reason for the bombs: were they set up in case he was defeated (with him detonating him just before he died), or was it always his plan to blow up the ship to get rid of any witnesses after killing Team JoJo?Also, how exactly did the ship blow up?