Now yesterday I downloaded the Nova Prospekt Metrocop cause it looked awesome and some work went into it (from what I see), but in Gmod it's head had a "Missing Texture" that was affected by light. Today, I downloaded the Metrocop Remake (Hexed) and went back into Gmod and seemed to have fixed the "Missing Texture" on the head. It looks like you will have to download this: https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=550957312 to fix it's head. I don't know if this is just from me loading up Gmod today (cause yesterday I didn't even bother restarting Gmod :P), but I would recommend downloading the Metrocop Remake (Hexed) anyway just so there isn't any other issues with the Nova Prospekt Metrocop.

Hope this helped! This is an awesome model/npc btw and I can't wait to see what else you create and upload Dead Astronaut!

Thanks and have fun! ;)