That is the unfortunate truth about a segment of this hobby. When NJT retired the final 13 GG1s they sat out un-protected for some time and were subject to theft of builders plates, horns, and general vandalism. I agree that it is best that these gems of locomotives are safely secured out of sight and out of mind.
Being preserved inside is something that most museum pieces don't have the benefit of which I find ironic. From the video, the locomotive seemed to roll very freely which I am guessing had something to do with being preserved indoors.