First of all, this is the xrs4900 forum, not the E5. Secondly, this is a Bell issue. All these companies (including netflix, hulu, disney, etc..) want boxes to be certified, in order to allow them and properly work with their crappy apps (for DRM purposes). Sometimes there are workarounds to be able to trick these apps to sort of work with limitations, but other times there isn't.
BuzzTV boxes are designed primarily as IPTV boxes, hence the BuzzTV app that is preinstalled on these boxes. For 3rd party apps, some will work, and some will not, and there is no guarantee or statement saying that anything else will work. I personally don't care for many 3rd party apps since IPTV services provide me all the media consumption that I need. However most of my buddies that use BuzzTV boxes for IPTV, often also have a cheap firestick or google streamer for all those other apps that insist on having "certified" devices to run on.
You can try using AptoideTV store (which is preinstalled on buzztv boxes), and you can install different app versions if you want to check and see if there is any other version that works. Otherwise you can try to find different versions at various apk mirror sites and sideload them to see if one works as you would expect it.
Good luck with that.