
I'm not 100% sure, but I think that more emoticons would have helped make your meaning more clear...

Even though my main goal was to be irritating with that first response, I actually think it has some merit. When you've got a book that has both sci-fi and fantasy elements, the distinction is blurry at best. I wouldn't be surprised in the least to see a couple magical things turn out to be mechanical, or vice-versa. Compared to the Inchoroi, or the Dunyain even, you have a bunch of primitive minds with effectively no knowledge of technology who have been living along side magic for their whole history.
That doesn't really answer the question though. More directly, it is easier for the reader to take a given character's perceptions/descriptions as facts, rather than try to twist them to some other obscure truth. A Quya, a Wizard, a Wich-to-be, and a bunch of superstitious madmen see Quirri as Magical or somehow divine.... right? Magic is more prevalent in the world than technology (at this point, (so we have been lead to believe)), so again, the magical explanation is easier. Also, the Soul seem to be the least common denominator in all things magical and divine, so by extension....
But consider two things: Most of what the Nonmen are today was forged by the Inchoroi and the Inchoroi did their experimenting before they could see the Onta. This would probably lead one to believe that since the Qirri is made from the ashes of what is basically an Inchoroi experiment, its likely that whatever the effects would be mundane rather than metaphysical.
Though, for the sake of argument, one could say that the Inchoroi are fully consumed by their desire to escape their damnation. This probably leads to an extreme obsession of all things Soul. Why wouldn't they try to develop, using their willing Nonman partners, some kind of meta-biological 'cure' for their condition? Maybe their experiments, while physical in nature, were designed to alter the Nonman Souls. Perhaps they succeeded. Still born children and dying in childbirth could seem like a problem with your Soul if thats what you're looking to find.
There, an answer thats not entirely designed to be irritating

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