Solomon Kullback, a professional who studies syntax for the Us Signal Intelligence Service, that is the study of construction of sentences and the arrangements of words and grammar usage in sentences, after studying the narrative text and the alleged "Beale letters", concluded," The writers of the two texts were the same person and the whole affair was a hoax".
With that stated, I do not believe the Beale Papers were written as a hoax, but as a dime novel with those ciphers added as play along parlor entertainment., and it is amazing that after 130 years people are still playing along.
As the codebreaker for the US Coast Guard's Division of Intelligence, Elizabeth Smith Freidman remarked after studying the Beale story and analyzing the ciphers at the request of the Harts," was printed for the express purpose of selling copies of it for profit, and the ciphers should be considered in the same light as the myriad 'treasure maps' which are sold in the southern states purporting to come down from pirate days".
With so many professionals in several different fields stating that the Beale Papers are either a dime novel written for profit or as a hoax, and the total lack of even the slightest reference outside collaboration that can confirm the Beale Party "perilous adventure", how can anyone expect to believe that a claim of a solved cipher is correct, when there have been many similar claims over the last 130 years after the job print pamphlet's publication?