The locomotive is owned by the Nevada State Railroad Museum. Before any equipment is restored it has to be thoroughly studied and documented in what is called a Restoration Report. The Nevada Southern Railway is simply the name given to the railroad consist that operates at the NSRM BC. The "Nevada State Railway" does not make any decisions in that regard.
In all there are 7 Nevada State Museums, 3 of which are devoted to railroads in this state: NSRM in Carson City, NSRM in Boulder City, and NSRM in East Ely. These ( and the other 4) are all under the umbrella of the Division of Museums.
As for narrow gauge track at the NSRM BC I have put down approximately 1/3 mile of track and plan to have about a half mile constructed before to long. That is what I run Eureka on during our Christmas train event in December. Certainly the EN 12 can run on it as well and maybe someday visit other venues like Carson City, which is now 3rd railed, except for switches. But that is sometime in the future, and not even on the radar screen right now. The EN 12 has to be restored first!
Hope this helps.
Dan Markoff