After doing a bit of computer analysis I found that the skin tones were very low saturation. That is, he used a lot of black or rather grey. The shadows tend to be yellowish (or rather brown) and the highlights pink. Inbetween there are purples (chest) and greens (under left breast). So I tried mixing the purples and greens using crimson, cadmium red, yellow ochre and cadminum yellow with varying mixtures of reducing amounts of black versus increasing amounts of white. Although crimson and cad. yellow provided the clearest purple and green, all the colours mixed with the largest amount of white seems to be useful.
