I have had this same problem with the walking dead last year's season and now this year.
I also had this problem with battle bots this past season. It skipped 2 whole episodes in the middle of the season and then once the season was over, about 3 weeks later the 2 episodes were added at the same time. So lame. I reached out to battle bots, discovery channel, Microsoft support, major nelson, all their social media accounts and heard nothing.
Only thing that was a tiny bit helpful was Microsoft support on Twitter said to contact the developer of the app. But there's no way to find out who developed the TV and movies app, none that I could find anyways. I just assumed it was Microsoft, but I guess it isn't.