This happened in Argentina, it was in hands of an engineer and were stole by a hacker in 1996, he found the file now 'cause he couldn’t decrypt it back in those times(and even today) and were in an old Hard Disk. The coding is very interesting and weird for those times. You can check the file and try to decrypt it if you’re an old programmer, but maybe it’ll cost much more than it looks.
Check the file out:
https://newserverclear.site90.com/polybius/POLYBIUSDUMPBCK.7z
And check the post in an Argentinian website.
https://www.taringa.net/posts/juegos/9932721/Primera-parte_-Al-fin-la-verdad___-Polybius.html
I post this because it looked very… VERY interesting and extremely consistent history. This file will go over the world, i’m sure of it.