As said above they do exist, a limited number of them had been initially produced and sold through another forum only.
I happened to be lucky enough to get one. Very well made lower. Not sure who made the lowers on that first limited run but I believe now they are being made by Mega Arms.
Suprised no one has said it yet, but yes they have the rights to the name, logo, etc. so there is no conflict to date with it being Resident Evil inspired. (from what was posted elsewhere)
ETA: They do have a pistol grip as well out, not sure if Magpul actually makes them but they did work with Magpul a while back in design per what I have read. See the link for the article I read with a comparison photo next to a Magpul. I have one of these on my Umbrella Corp. lower, comfortable and like it so far.
http://militarytimes.com/blogs/gearscout/2012/09/13/umbrella-corporation-ar-15-rifle-grips/