An ex-GM from a site said this:
There is a particular mining camp which I dont believe many people have seen ever. Its a bit of a mission to get to, but basically looking at the map of Gadgetzan you will see there is a circular map symbol just off the coast in the south. Swimming there and straight down will lead you to the camp (you will need a pot to breath underwater or a friendly neighbourhood warlock)
I tried it but couldn't find anything. Maybe if you guys could check it out and tell me if you see it, that would be great!