>>All that I know of the title is that it appeared with the image on his prints-for-sale. So I can say “photographer’s title” confidently. But I cannot say how he arrived at that title - whether he dreamed it up, read it on a nameplate or artist’s inscription, someone suggested it to him, etc.<<
Understanding that the photographer was selling photographs and that this is from a Graveyard AND looking at the other titles, one can safely state that the titles were names by the artist of his photos.
Unless one thinks that plaques like “Graceful with Granite” are on gravestones.