Here's some work I did on my door last year Jason, unfortunately you have rather less area to work with! However I notice you've found the pale green colour, which appears to be some kind of gloss repaint prior to DBG. It's an entirely different formulation to the matt paint coats, you'll find it goes quite soft when rubbed back wet, and tends to peel and tear instead of powdering, much like cheap plastic house paint. The pale grey colour you're seeing underneath is heavily oxidized, you'll find it's considerably darker when rubbed back slightly. The reddish colour you've found underneath is yet to appear on the door, which would seem to indicate a disruptive pattern. Likewise the sandy colour only appears in certain areas on the door. If you work carefully in this area you should find the factory camo underneath, however I don't know what part of the vehicle you've photographed so I can't say whether you'll find Light Stone pattern.
Evidently these two NT Force FGTs had a rather unusual camo scheme applied in service, and it's interesting to speculate on what it may have been. Following are the camo schemes approved in January '42:
Three-Tone
1. Light Stone N. Light Brown P. Khaki Green J.
2. Light Green H. Khaki Green J. Black U.
3. Light Stone N. Light Green H. Khaki Green J.
4. Light Stone N. Khaki Green J. Dark Green M.
5. Light Stone N. Light Brown P. Basalt Red S.*
Two-Tone
6. Light Stone N. Khaki Green J.*
7. Light Brown P. Khaki Green J.*
Instructions stated: "The colour combination selected should approximate to the colours of the country in which it is expected the vehicle will operate......For Australian Central and Northern Areas use Set No.5 or 7."
There are many twists and turns to the story, but it's possible the two disruptive colours we're seeing are Light Brown and Basalt Red, used with the greyish colour no. 6 in pic 3, instead of the prescribed Light Stone of Set No.5, which as a Middle East colour had been found too light for anything but desert use and discontinued. Such a combination would approximate Set No.5 as originally conceived, adapted with the benefit of experience in the field. As for colour 6 there are several possibilities, including approved colours such as Slate Grey or conceivably Darwin Stone....whatever that may be! Of course, a further range of possibilities exist in relation to the other two colours, for example the sandy colour may be Warm Sand, which was added to the range in September '42.
I'd be interested to learn more about camo schemes used in Central/Northern Australia, as they may be worth considering instead of factory camo. Certainly they'd be more authentic on these NT Force FGTs.