That image showed up in NCDOT’s official Comprehensive State Rail Plan in 2009. Attached here:
2009_railplanexecsum.pdf (1.7 MB)
It was gone for the next (and still current) update in 2015, replaced with this one:
I have no idea what was behind its appearance and subsequent disappearance. The 2009 plan did not say much about it, and the 2015 plan says nothing about its removal.
My best guess is that they are still not thinking of doing this, based on the fact that they are studying a bunch of corridors across the state, and submitted an even larger list of corridors for the FRA Corridor ID program, but this isn’t on the list:
