The info is right, as is your evaluation.
On the OEM parts Apple's using, the naked CPU and VR's are the same height, and make contact with the copper surface of the heat sink.Commodity W55xx/W35xx/17-9xx parts have the IHS, and will end up breaking contact with the heat sink and VR's. Using the mechanical drawing Intel provides, the gap will be 1.845 - 1.895 mm. in height that has to be filled.
If you know of a good product that can do the job, it might be helpful.
The GapPad material I linked has good thermal conductivity, is electrically non conductive, and comes in thicknesses that can do the job without the need for multiple layers of it. As a price example, I found the 1500 series, in a 4" x 4" sheet, 3.18 mm thick (1.5 W/m-K) @ $20.30USD from DigiKey (here). It could be used, but personally, going through this much hassle, and not sure how hot the VR's are getting (only estimated), I was thinking a better thermal conductivity was in order, and was thinking more along the lines of the 2500 series material.