Here's the documentary referred to: https://www.imdb.com/title/tt21945758/
It's rentable at the usual places. I might check it out.
There are stories about bodies of Christian monks that did not decompose for a log time after the dearth. Modern take on it attributes it to the climate in caves where the body was put after the dearth. But another important part was diet. Often the well-preserved bodies were of those who had eaten only rough bread and water for months and years before the dearth.
So I suspect both of the factors are at the play here as well.
I think you’re referring to the phenomenon named “incorruptibility”:
https://en.wikipedia.org/wiki/Incorruptibility
Recent case, died 2019, found not decomposed in 2023, had not been embalmed, unsealed wood coffin:
https://www.ncregister.com/cna/incorrupt-body-of-sister-wilh...
If TRUE and consciousness is eternal (using whatever framework you like), the idea of death becomes double sided. On one hand, physical death is sad as it's the end of this physical 'epic story' before our consciousness moves onto a new body/story. On the flip side, approaching body death is a sort of a temporary great relief as we are immortal and cannot actually die. I.e. After ten thousand years of being alive, a vampire looks forward to sleeping in their coffin at night.
The research mentioned in the article (which indicates no EEG activity): https://pmc.ncbi.nlm.nih.gov/articles/PMC7876463/
One of the referenced articles is a wilder read, just even from the title: “Decapitation in Rats: Latency to Unconsciousness and the ‘Wave of Death’” (1).
This research is more than deserving of the Ig Nobel.