This is a strange connection of events. Pieces of the story are reminiscent of the Dead Sea Scrolls.
--A clay jar with books inside, found in a mountainous region honeycombed with caves.
--A little bit of black-market dealing before the find is publicized
However, there might be differences.
The Dead Sea Scrolls site became the focus of a careful search, eventually revealing much information about the religious community that lived at Masada and stored their scrolls in those caves.
Also, the scrolls that were found were turned over to a group of scholars who worked in Jerusalem. If I remember right, a noteworthy (and interfaith) group of scholars were involved in the study, and worked through a university in Jerusalem...
A last detail--the original finder was a Bedouin boy, looking for a lost sheep in the caves.
What about the discordant details?
--A blood feud?
--Farmers searching for soil (in a mountainous region full of caves?)
--Lack of provenience information
I wonder if the blood feud was more related to the search that discovered the scrolls, than to the death of the father...Or if the blood feud had anything at all to do with the events. But if it was entirely disconnected, why was it mentioned?
I think the blood feud is mentioned to explain how the codexes ended up in the hands of black marketeers. The brothers were afraid, after they killed the man whom they blamed for their father's death, that the police would search their home. They took the books to the home of someone described as a village priest (the name, if I remember rightly, appears to be Muslim, but I may be wrong -- he may have been Coptic) for safe keeping.
I guess my major point here is that it's impossible to draw inferences from story of the find. While the codexes are certainly an important find and well worth the scholarly attention devoted to them, the lack of provenience makes it impossible to draw any conclusions as to why or when they were buried.
It's also possible that the story of the discovery of the books is entirely fictional -- that they were not found in a jar, or found where we are told they were found.
Looters of archaeological sites have good reason to be dishonest about where they find what they find.