The facts, and the real facts (maybe)

Well, no one else has seemed to chime in with any support, so my guess is that it's just another one of the inaccuracies that plagued, and continue to plague the community. My guess is that it's probably referring to some D&RGW car, if NG at all.
It's probably not the 56 because I don't think that Mr. Drawer got that car until much later, 60's or 70's. Until then, I guess it was on a farm. (I've also heard that another ex C&S coach was acquired by him, but, believe it not, was even worse off, and didn't last long. Anyone confirm of deny?). And as we know, the 56 was far from complete.
It's sad to think of how much C&S equipment has been lost since abandonment.
Caboose 1008
One of the St. Elmo Boxes
The Tiffany Reefer in Leadville
Two combines in Leadville
Two passenger cars at the end of the Silica Branch.
Two passenger cars in Longmont.
A boxcar at Sunset, and I'm sure others
I've heard of other South Park freight and passenger cars existing at some point at Wheeler, Nighthawk and other places, although on farms...nothing like the complete car mentioned in the book. Unless somehow the author took the 911 to be privately held...
But we can dream...and this is one of those times when I'd love to be 100% off.