First, few remarks to the "cosmology." Existence-consciousness is all there is. It is unchanging, without attributes, unsubstantial, and the immortal ontological basis (or rather, concepts of life and death don't apply to it). Furthermore, it cannot be adequately named in an unambiguous way as naming it immediately puts it in the category of things "out there", which it is not. This "ontological basis" is also known as God, Tao, Brahman, Buddha nature, etc. And we are that.
From this “fundament,” which predates also time and space, then universe arises. But universe is nothing more but that unmoving existence-consciousness in motion. Or rather appears to be moving, akin to a mind-bogglingly structured and consistent dream. How the unmovable starts to move, or how the illusion of movement arises, seems to be a total black-box -- the deeper the observation directed outwards goes (science) the less sense it all makes (it always just seems to go deeper and deeper without any clear resolution), and neither introspection can reveal the mechanics of the arising itself (though it can reveal the actual mechanics after the fact, but it's really almost impossible to put it into words -- you have to "see" it for yourself).
"Akashic records" are then universe itself in its current state (it is always in current state btw.). Since this current state is the result of all past causes and effects they are contained in it exactly as e.g. your parent's genetic makeup is contained within you, etc. It's not a metaphor when people say that all of us are stardust or that we all were at the Big Bang -- the "stuff" we are was literally there. "Akashic records" also don't contain future. It's our brains that create (rather accurate) simulations of future from current state by inferring the general causal trends. And due to many factors (randomness, free will, etc.) no future prediction is 100% spot on (they could be plotted as a standard distribution though). So, "reading Akashic records" is just reading universe, fundamentally no different from everyday interaction.
When it comes to NDEs, first, they were all just near death. Second, even after clinical death the processes in body don't stop immediately. For example, in Tibet, they read Bardo Thodol to a deceased person for several weeks before they dispose of the body (considering the geography of Tibet, the metabolism and decomposition must be significantly slowed down). Third, brain (and CNS in general) cannot be separated from the rest of the body -- it's body as a whole that generates cognizable experiences. And lastly, such state (i.e. NDE) is the pinnacle of altered state of awareness.
Taken all of that into account, I don't see why a person would be unable to "meet" unknown relatives with whom they are physically linked, or why they would be unable to "recall" someone in their particular causal stream who contributed to some important factors of their circumstances in a significant way (the same also applies for all the so-called "reincarnation memories" and OBEs).
As for "spirit guide councils" and similar (and crazy particulars of reincarnation that differ wildly across the traditions), when I looked at people with such claims, it always turned out that an already established belief predated the interpretation of the experience. So, there's that.
And all of the above can also pretty much explain interactions with sentient people and other entities that are "not there" but can communicate valid and verifiable information.
The "souvenirs" are, indeed, a literal mindfuck. To be honest, I don't know how to explain them. I just always find it curious that most of those Harry Potter style mysteries come from UK, exactly as UFO abductions and similar are predominantly a domain of USA lore. Be as it may, I'm firmly convinced that there is a natural explanation for them, even if it may be a rather unconventional one (by current scientific standards). With that being said however, yes, vast majority of such reports are simply hoaxes IMO.
Ah, and the many worlds interpretation -- yeah, it's basically BS. I entertained it just for the sake of argument.
