> Start by explaining how there can be any experience at all after an hour without oxygen to the brain.

Some cells are still technically alive after 1 hour mark in the sense that there is no necrosis and cell membrane is still operating. This depends on cell type and nourishment - for example cells that have high amount of CoQ10 can live longer etc.

In any case, brain is definitely NOT 100% dead in a sense that ALL of its cells are necrotic which might explain why it is in a dream like state.

Also, I doubt 1 hour mark is regular thing in NDE.

How would we determine that the experience happened during that time and not as a memory created when oxygen reached the brain after, or so on? If you assume that narrative memory is a little bit hallucinated (which I think is pretty observable, try dissociating a little and you can experience it) then many options are on the table.

> Start by explaining how there can be any experience at all after an hour without oxygen to the brain.

Besides the clear possibility that the memory forms later, the brains of people who report NDEs have never stopped - there is no report of anyone ever recovering from brain death (as in, from a basically flat EEG).