well, you've got two options on this one as I see it.
your subject was wither given the RAF color scheme in the factory, or by the RAF at a receiving depot (or whatever they were called). either way, the pictures you have are clearly of a restored aircraft, so you cannot depend on the colors in those photos being accurate (though they are probably not a bad guideline as to what the real ones might have been).
So, if is was a factory applied scheme, it would have been "equivalent "colors - something like ANA613 (olive drab/dark green) and ANA617(dark earth), and ANA610 (type 'S' sky). these are similar too, but not usually the same as the RAF colors (actually, the sky color is quite different). Often times, normal USAF olive drab was considered a fair substitute for RAF dark green for expediency's sake.
But since Dakota sub-assemblies were made in different factories, pre-painted, and then assembled in another place, I seriously doubt if the camo would have been factory applied (you don't want mis-matched parts). I could be wrong about this, but I think Dakotas were only supplied thru lend-lease via US army stocks, so that would help confirm this notion (though not actually proof, because in the case of the p-40, for example, the USAAF took on many examples of aircraft painted in RAF equivalent colors that were factory applied, but again i do not think this is the case for dakotas)
this means the RAF repainted the machine upon arrival into their stocks (but probably before assgning it to a unit). Question is, how thorough were they? did they just spay RAF dark earth over the factory olive drab and neutral grey? Did they also paint the neutral gray over with RAF sky (an odd greenish gray color a lot like the one you see in those pics), or did they repaint everything? No telling now, as clearly everything has been repainted (probably several times) on the aircraft you have the pictures of.
If we are going to go by your picture, then I would say go with the who RAF scheme. Usually RAF sky was used with the dark earth and dark green combo. Medium sky gray was more often used with the dark green ocean gray combo. Plus it clearly looks like they are going for RAF sky in those pictures. If they made an attempt at matching the original colors when restoring the machine, then that is clearly what they were trying to reproduce in this case (of course they just might have gone with what they thought was correct and not bothered with what was actually there).
hope that makes things as clear as mud for you...
