I tried your suggestion and tested the camera outside. It stopped raining just long enough to make a quick test. I wound up with pretty much the same results using the 24-70mm 2.8 The other two lenses I have are the 14-24mm 2.8 and the 80-400 VR, I didn't bother testing with those. I have a 50mm 1.2, Of course it's manual focus, maybe I could test with that one. I tested the same setup last evening with my D3s, no issues with focussing on that camera body.
Yes, it seems the sereial numbers are different from the D800. They seem to be lower in the sequence. FWIW... Another Nikonians member purchased an 800E from B&H during the first week of January, his serial number is 2000+ higher than mine. Your camera is around 2700 higher than mine. That leads me to belive my camerea an earlier production. How much earlier I'm not sure, I can tell you though, I'd prefere a higher serial number like yours.
I'm glad to read that your camera is free of this left focus issue. It gives me hope that I may be able to aquire an 800E with out this issue as well.
"Things are'nt always quite as cherry, as they first seem"