Re:A Nepali team has made the first winter ascent of K2
by outside1234 on Sunday January 17, 2021 @09:16PM
(#25817436)
There is also mysticism in some Asian cultures about photos and taking other peoples photos around stealing souls etc.
This potentially could be a reason as well that he wasn’t brave enough to admit.
I'd be very surprised if a man of Tenzing's calibre and achievements could not figure out something so trivial.
Edit: I've found some citations that support your point, I apologize.
Although, I'd add (a) Tenzing's account states that he offered to take a photo but was declined. And (b) a more fair description would be "because he had never used a camera before" rather than "didn't know how to work a camera".
The later suggesting a lack of intelligence or civility (though I'm sure that wasn't your intent), I'm probably just nitpicking :-).