Sorry then I run out off idea's but you could try uninstalling an app and install it again to see if this works and or check in the store, in the review of the app, if more people had this problem.
I doubt that anything like uninstalling/reinstalling is going to help here. Neither do I believe that other people suffer the same. It's just plain weird that he's getting toast notifications, yet the tile isn't updating when being on a cellular connection. Yet the tiles DO update, when he's using WiFi. That just doesn't make any sense at all.
A hard reset is a "last" option and Itsmewasim should decide if he want to do a hard reset "just" to get the live tiles back.
And also then there is not a 100% guarantee that this will help.