The file comes from copying Ektachrome on the D700; no, I don't try to emulate any 'filmic' look at all - just to produce something that looks reasonably nice to me on the monitor.
Okay, so maybe it is a combination of factors. I can't comment on the Nikon software, as I don't have any experience with it, but if PS is complaining, then there may certainly be something fishy happening.
Additionally, if you use your camera to reproduce a reflective print, then the most important step, and the most difficult step I'm inclined to add, is to "calibrate" the blackpoint. You have to somehow try to obtain neutral blacks before doing anything else, because reproducing a reflective medium will also mean reflective blacks. And those blacks will have a colorcast which is far more sensitive to balancing than lighter grays and white. And changing the blackpoint will have a significant effect on the overall result.
The preferred order of steps would be:
1. neutralize blacks and select the absolute black point location
2. neutralize the entire graybalance
#1 above defines the origin of all the mathematical multiplications and other BS necessary to make a pleasing picture. If the origin is out-of-whack, then anything subsequently is going to be a juggling act between different parts of the image going out-of-whack.