He can still refund and if he wanta to refund we can tell him how to do it. He will simply just be banned. Unless you asked a higher staff about this I dont think you should have closed this thread. Instead... The Opti so he can take care of this because he is the one to control the store and bought ranks.
Ok, I agree that they do have the right to chargeback, but if it is against the rules on PrimeGames; why would we be the ones to explain to them on how to get a refund? The server would be losing money and if they really wanted to chargeback, they would do an internet search which would give them a detailed explanation on how to do so.