Post processing volume colliding with skybox

Hi everyone

I am using plugin from npruehs called RTS Plugin which has implemented fog of war using post processing volume and a fog of war material that draws black wherever we dont have vision.
Problem is visible on this picture

I would like to enable this postprocessing on my actors and terrain but exclude it from skybox. Or if that isnt possible, it would be nice that skybox and posprocessing volume arent fighting like its seen on this picture above. It doesnt change even if i set Postprocessing priority to higher
Any tips would be sweet.
Thanks