boat leaderboard friends rank not showing with 5568 points

Hi. A friend of mine not connected to Facebook is not showing a rank on the friends leaderboard.
They have 5568 leaderboard points so this should not be the issue. I am friends with them through the game centre.
why don't they have a rank? They are on level 44 at the moment. They have also completed the filling ten boats in a row challenge.
thanks!

I believe it only shows if they are in top 2.5 millions in global. It should be about 8 or 9 k points.