I have started a new game, and traded from my other sav file all of the 5 pokemon required to be given for the quest.
So now all you guys gotta do is self-trade by opening two games side by side, and then to trade the respective pokemon. (I have attached the save file, you jus need to copy it to your saved games folder).
If you guys are stuck, lemme know so I can trade the appropriate pokemon with you.
Game_7.rxdata