My partner and I had done this quest (he was able to finish it) but I couldn't, I got the replica sword and then as soon as I came back from the dungeon map with the sword, Yoshi directed to me with my partner's username and then told me to talk to Damien, so I did and it put me back in the island. I redid the maze and went back to Jamie with the sword to which he responds "We have to absolutely win this" (something like that) I've done the maze 6 times now and I can't seem to get the quest to finish despite having the sword.

My only option is to talk to Damien but all he does is send me back to the maze map with the same dialogue.