On this page: https://developer.apple.com/documentation/tvservices/tvtopshelfcarouselitem/mediaoptions we see a full list of the possible MediaOptions applicable to a Carousel item.
However, the built-in TV app appears to show some extra ones, see this screen capture: https://www.dropbox.com/s/ranhkgkj64xopxx/Screenshot%202019-09-13%20at%2018.23.33.png?dl=0
Any ideas?