I have just bout a 2016 Discovery 4 - my first Land Rover so I am a bit of a novice. The vehicle is fine except for the factory fitted rear camera which is all foggy and I am not sure if it is scratched glass or moisture inside the lens. So I want to take it out and clean or replace. The camera is in the same housing as the number plate light and the tailgate lock and seems to be fixed with 3 screws which I have removed (see attached picture). But the assembly won't budge and I am reluctant to use brute force yet. Is there a trick to get this out? Any advice appreciated.

3 screws on bottom removed