do you have multiple rokus? Does it work ok on another different roku?
I ran into a crazy issue a while back when publishing a channel that is similar. I could NOT figure it out for the longest time.
It turns out that i had saved a setting to the registry that became invalid during development, and the setting persisted on the roku box through uninstalling and reinstalling the channel - and a side-loaded copy of the same code on the same roku worked just fine. But the channel worked fine on every other roku box I tested and the code was good. The only way the value could get there was during development, so it wasn't even an issue, but just on that one roku it didn't work.
Now I use different keys during development and testing than for publishing to eliminate this.