I discovered this song in the book "Folk-Songs of Virginia" by Arthur Kyle Davis Jr, but sadly the book is only a list of songs collected in another book, "Traditional Ballads of Virginia" published by Harvard University Press, 1929, so there's no lyrics or sheet music provided. The entry in the section "Ghost Ballads" is as follows:

"The Christmas Ghost. (“Lone Farnby’s Moor lies bleak and bare”) Contributed by Mr. R. E. Lee Smith, of Palmyra, Va. Sung by his brother, Mr. Thomas P. Smith, of Palmyra, Va., and himself. Fluvanna County. October 21, 1931. Four stanzas."

I got an update courtesy of the Small Special Collections Library at the University of Virginia, minders of research by the Virginia Folklore Society. Luckily they obliged my out-of-state email request for the transcription. It's not much but this fragment is eery and mysterious:

"’The Christmas Ghost.’ Contributed by R. E. Lee Smith, of Palmyra, VA. Sung by his brother, Thomas P. Smith, of Palmyra, VA and himself. Fluvanna County, October 21, 1931.

'Lone Farnby's Moor lies bleak and bare,
No living traveler anywhere.

The frozen earth is cold and white
Upon this dreary winter's night.

Ah, how the chilling night winds grieve
Across the moor this Christmas Eve.

Such cheerless scene not oft you'll see
At Christmas in the North Countree.

Some miles away o’er Farnhope's height
The silvery moon comes into sight.'”

If anyone has any knowledge about this song or related variants I'd appreciate it!