The fixed position of moonlight jewelry on Black Curse Island can be found. It is difficult to describe those wicked positions without screenshots.

You remember that there is a cliff just above the top of the main entrance of Black Magic Island. You can jump on the post and follow it to the island in the sea (the island with a sharp point on it is next to the boat). Here's an ending image.

Go through Black Curse Island, come out of the last boss room, and you can get to the top of the main entrance.

Zhou Mu can actually do it, but cg animation will send you directly to the woman in black, so it will take you two weeks to get this moonlight gem and the ending image.