The differences are very subtle and certainly could be why they have been missed before or that I am wrong (if you see what I mean).
If you look around the vicinity of BCD there are a lot of rocks with these 'cut marks' some of them still have their inclusions where calcite crystals have formed. Woody textures also often appear in a variety of rocks.
The main reasons I think the pillar is different are that the 'cuts' are very untidy for this type of crystal inclusion, and the different woody textures (of bark and exposed grain) appear on all sides. They couldn't have been cut and a natural cylindrical pillar with those textures would be even more extraordinary.

I hope that makes some kind of sense. Trying to avoid paragraphs of rambling after a few glasses of red