Interesting idea I hope your find people engaged with talent to write your story.

That could have been interesting, but I don't have the first requirement of Warhammer 40K, only a brief overview in some videogames.

I'm more knowledgeable of the StarCraft univers, Warcraft (not so deep of World of Warcraft), Lord of the ring and various LARP background, StarGate, starwars, a bunch of StarTrek and many sci-fi such as Fondation and Robots of Asimov, Ants of Werber, NonA from Van Vogt.

But I agree that your needs will be better served by a fan of Warhammer 40K. I could have creativity and original ideas but they wouldn't grab context of your world which is the escence for core fans.

Goog luck again with that "contest" ;)