While not a PDF, the YouTube channel "Archivo Denegri" (unofficial) has hundreds of clips. You can transcribe these clips to build your own personal PDF. For linguists, this is actually superior to a static document because you hear the pronunciation and intonation.
Published by (2019), this 300+ page book is the closest thing to a Denegri PDF in print. It contains 180 entries of his favorite rare words. While not a complete lexicography, it is the authoritative source. You can find it in major Spanish bookstores or as an eBook (EPUB) – which is better than a scanned PDF.
