It's in 2.3. It's located at the top of the Camera and Lens Correction section, but it's suppressed and not visible unless you have a raw file open. It doesn't need to be a D800 file - any Nikon raw file should work. Something that seems unfortunate to me is that it's a global setting rather than a local one (a la NR4). That means the entire image could be affected by activating it (it has low, medium and high parameters), but in quick experiments I did with other raw files, cranking it up didn't seem to affect the image as a whole, so maybe it's quite smart and will attack only areas where it perceives moire. If that didn't work you could always generate two conversions out of 2.3 - one with moire correction active and the other with it inactive, layer them in Photoshop and then paint in a portion of the image with the correction enabled.
BTW, my personal experience with higher res (not as high as the D800) cameras lacking an AA filter is that moire didn't show up much at all in my photos, but the images sure looked nice. It was a pretty rare thing to see it, and I really had to hunt to find it. The D800e should be a bit better for several reasons, so I'm not expecting a big problem on that front for the kinds of things I do. I have three different software packages on my computers that will remove or diminish it (LR4, Capture One, and NX2), so I figure one of them should work. There are also more cumbersome techniques in Photoshop, but I think I should be able to avoid that. Some of this we won't know until the camera is out in distribution and some experimentation can be done.