My Game Theory professor in college was a huge movie buff. I also took his Economics of Movies class as an elective, lol. Joke of a class but it was just an elective anyways. At the time I took his Game Theory class, this movie was his favorite movie of all time. And we studied the Boat Scene just like you mentioned, as the Prisoners’ Dilemna. They did the right thing by not doing anything so they would have scored the highest possible in the matrix (although the highest score should still involve some type of negative consequence for the people involved). In the movie they didn’t suffer any consequences, I don’t believe.
This movie used the Prisoners’ Dilemna a couple of times. I don’t remember the movie too well but I remember my professor geeking out at the different times the Joker put people at odds in a game in the movie.