iPad 2 (iOS 8.4.1) Videos app says "no content" until connected to network

I have an iPad 2 (32 GB) for my son that we use for learning games and the occasional movie. We were recently on a long car trip and we gave him the iPad to watch Rio 2 that we purchased from iTunes. We have watched this movie many times, and have not had this problem before, but when we last went to watch the movie (just today around 2:00p CST) the Movies app said "No Content". We could not get the movie to show up until we turned the hotspot on my wife's phone on and connected the iPad to WiFi via her iPhone. Once it was connected to the internet, it showed the movie. We then disconnected from the internet and the movie played just fine (confirming that it was actually downloaded for offline viewing). What troubles me is that this iPad is only WiFi, and if it requires a connection to the internet just to start playing a movie, it is going to become tiresome very quickly.

Does anyone know what might cause this?

Thank you in advance,

Chad