Rebel,
Check into more infomation about it. There wasn't just Charle's island listed in the stories about him. But, they are all on islands. You need to rent a boat to get to any of them. (Well, Charle's island is said to have sand bar access, and Kidd's island maybe with a hot dry summer you can walk across? idk how deep it is there).
I used to have a buddy that looked for all kinds of local treasure. I went with him a couple of times. We never found it but I do remember being waist high in a small river thinking "why aren't we walking the shore". That was it for me:lol: