We’ve actually just identified an issue here. It looks like a bug with shows being displayed if they were already watched. While we investigate, as a workaround for now, use your Android app to access an airing of a show that’s not appearing on Roku, and begin watching it. Then feel free to back out. This should reset its progress to the beginning and should now appear in the Roku Library.
We apologize for the issue, though for now it seems to only affect already watched recordings.