Don't get me wrong, I realize it's not as simple as "unlocking" the area. Even if the Ground Zeroes assets are completely intact in TPP's files somewhere, I know it'll still take some work to hook all that up so that the player can access it. Even then with Metal Gear not really opening itself up for modding willingly, it would probably have to be accessed through an Infinite Heaven menu or something. I'm just pretty surprised that with how surprisingly active and dedicated TPP's modding community is, no one's done it in six years.
Is there anyone working on this at all?