My "edition" is definitely not an [urtext](https://en.wikipedia.org/wiki/Urtext_edition). I made minor simplifications to the descending line at measure 8, following Lang-Lang's performance (which I believe is the correct decision - the arpeggiated diminished chord F-D-B-G#-F-D sounds better without any gaps, compared to what's in the scan, B-F-B-G#-F-D.), and added some phrasing where I thought it was obvious and perhaps went missing over the ages from the raw scan. The ornamentation in measure 20 was probably modified by Lang-Lang, but I think it fits the piece better than a plain mordant, so I notated it as played.
If I were to judge based purely on the music - minus all of the contextual clues like paper, ink, backstory - the probability of it being fake is ~10%. I say this only because it is shockingly similar to 34-2 in harmonic and stylistic elements, which is exactly the kind of thing an AI trained on a not-big-enough dataset would do. While AI utterly fails at longer pieces, it could plausibly render a coherent 24-measure piece in the style of Chopin, and DeepMind could plausibly be working in stealth on a really good music-composition AI. But in the end, the piece is too tightly composed, and I trust NYT's decision to trust the historians who are familiar with evaluating such artifacts.
https://www.moderndescartes.com/essays/chopin_waltz_posthumo...