if u have bow or boomerang it should appear

also make it nighttime. if u dont have the wind waker spell to change between night and day u can get it at windfall island

I tried sailing day and night around the entire quadrant and I could technically go to the final dungeon of the game.

I was able to fix it by restarting the save file and defeating it before the 3rd dungeon, whivh I had no problem with because the game is really fun.