I imagine it should be pretty straightforward to show rotten tomato ratings in the guide.
It would be really great when tapping on a movie, to have a summary of the rotten tomato ratings for it. There is loads of space on these views so adding a bit more info would surely be easy from a design point of view and presumably not hard from a coding perspective.
My suggestion would be that the critic and audience scores are inserted in one of the locations (red or blue) as indicated in the image below.