This occurs on maps that are completely indoors and are ment to be rather dark. It makes the lighting much darker than it should be, also lights seem to not effect the floors. When you get assassinated you can see the correct lighting.
I have linked my map on i posted on forge hub HERE that it occurred on (It has also occurred on one of my friends map too). In the photos you can see how the map should look and how it looks when you get assassinated. You will see when you open up my map in custom games it looks a lot dark than it should and that the lights dont effect the ground blocks.
EDIT: i spelled Broken wrong in the title…