Hi,
If I recall correctly, when RGS was part of the D&RG(W), work was done at what might be excessive prices. It may have been the desire of the D&RG(W) to get a price to the show a profitable shop repair account for the D&RG(W) and to allow the RGS to show an expense so the RGS could show an unprofitable bottom line that could be deducted as a cost on the D&RG(W).
During the receivership/reorganization that occured before the Geese were developed/built, the RGS was separated from the D&RG(W) and as many items (cars, shop work, locos, joint terminal costs) were returned to the RGS.
I'm not sure of the details but I'm missing a few books and cannot verify it. I think it was much like the Southern Railway, PRR, UP, SP and many other railroads had subsidiaries that allowed creative accounting.
Sort of like Southern's 6900-6915 E8's being lettered Southern. Those owned by CNO&TP (6904-6915) had a small CNO&TP on the cab.
Doug vV