Are Game Center friend relationships supposed to be private? What if scores on a leaderboard allow anyone to infer some friend relationships with high probability? Would this result in app rejection by Apple?

The reason this would happen is because I am thinking of modifying scores before submitting them to Game Center by adding to them scores of the player's friends from the last day.

Are Game Center friend relationships supposed to be private? What if scores on a leaderboard allow anyone to infer some friend relationships with high probability? Would this result in app rejection by Apple?
 
 
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