That's a good one, but I don't know. Most small developers don't keep console players in mind for their games, especially games like these. I don't think that it's going to work on Xbox unfortunately.
E: You can't try to get the keyboard on-screen manually? Like, a button you can press for that or some option in the settings menu? You've probably already tried that, but anyway. If that doesn't work then I think it's safe to say that the game is unplayable for Xbox.