I think the truth was uncovered. Beyond that Hakan/Christakis, his mother, and Politis wanted to protect him and his family so they closed the story the way they did. After all Christakis is now Hakan, and he would have to continue living with his family in Turkey so it is enough for him and especially his mother to know the truth, and the rest of us can think whatever we want to think.
Of course we wouldn't mind to use this case to score some points against Turkey, but in this case attempting to do so would be self defeating since such thing would put in risk the life of the only missing person found alive so far. So even if the government knows the truth I don't think they will ever say anything.