Many mobile players don't read their wall posts and messages. As a matter of fact, lots of them don't even know the existence of PC side of the game such as profile page, forums, etc.
I, for instance, discovered the game from Android Play Store and for about two months, didn't know at all that the game was actually PC originated, believing that it was totally mobile thing.
If you know his email, write him there. You can also try to message him on mobile. There is a chat section in the country club menu so maybe he'll be able to check your message there.
Good luck!