Maneater has been out for a couple of days, and players have been running into the occasional bug. The Queen of the Ocean trophy is one such bug. You can get the Queen of the OCean trophy by completing everything in the game and getting each region to 100 percent. This means collect all the license plates, nutrient caches, and landmarks, as well as finishing every mission, side quest, and trophy in the game.
Unfortunately, some players have been putting the work in, and not getting the trophy, despite getting everything to 100 percent. According to a post on the official Tripwire Interactive forums, the developer is aware of the issue and is working to fix it, but cannot provide a date when it might be fixed just yet.
Now, some players have reported that they got hit by the bug, but managed to resolve it by open the metal gate in the southeast corner of the Golden Shores area. To open the gate you will need to catch a fish in your mouth, then jump from the water and tailwhip the fish onto the button that opens the gate. It is not the easiest thing in the world to do, but with a little bit of practice you should be able to hit the target.
While this is not guaranteed to work for you, some players have reported that doing this got them to 100 percent. Other than this, all you can do is wait until Tripwire resolve the issue and you can finally get that 100 percent completion.