When searching through the rather more dusty sections of the Oberwolfach library, I came across a strange journal called "The Library of Lost Axioms" from the 1970s which as far as I can tell has never been digitised.
If anyone has any information on this journal, or has any further editions, please email me.
UPDATE (15/06/2026): Thank you to everyone who emailed me with enthusiasm and clues. With your help, I was able to contact one of Jonathon Fieldmann's students who was kind enough to look out and send one of the copies he still has:
Apparently, The Library of Lost Axioms was in publication throughout the last quarter of the 20th century. So it is still confusing to me why, to my knowledge, none of the editions have ever been released digitally. Why Jonathon's student couldn't find any editions from the 80s or 90s is also weird. The whole thing seems too pointless and random to be a hoax. However, I cannot find much evidence that a Jonathon Fieldmann ever existed, outside of some odd papers in relatively obscure journals. Could this be some sort of Bourbakian figurehead? The only relevant anagram I can find within the name is 'manifold', which seems lazy. It just appears unlikely, from the number of emails I received, that this theory holds up.
I believe that there must be some office or hard drive somewhere that contains complete volumes of issues. I've been able to track down more people who were in the sphere of LoLA, or know those involved in making it. Hopefully more updates and issues on the way when I can get them. Stay tuned.