No conclusion was meant on my part Bigsciota. Also comes to mind is that ceremonial flutes might be very well kept, for example. Some cultures also are just very much that way. For the six holed flutes
https://www.flutopedia.com/brokenflutecave.htm
is what I was remembering, but there are all kinds from the region, and in many regions. However usually any region or culture will have a distinct set of flute types easily identifiable as its own.
I’m no expert on the theme though 
.
It could have been used like this flute:
https://www.youtube.com/watch?v=VbNoqhdSjAQ&t=1s
It’s not long enough to get that many overtones, as I think someone already said or implied.
It is about half the size of a tin whistle ? What was noted before is that a tin whistle can reach various overtones e.g.
https://m.youtube.com/watch?v=aPrP3f0utKk
And other effects as well.
Plus there is one tonehole, plus the end can be covered to whatever degree chosen. I think that would give some scale.
The thing is this, a lot of the instruments linked above are fippled. Some ancient bone flutes were quena like it seems though, and to me it seems like this is a line of instruments in Europe that dissappeared somewhere along the line. The Ney or Kaval are true endblown but without notch , and are positioned differently to say a quena. They are implied as more recent near eastern origin also. The there is the svirel from Russia said “end blown” but I could not find an example of one that was without fipple. Then there is the greek flogera, this one seems notched, if it is one
https://www.metmuseum.org/art/collection/search/505130
And this says rim blown
https://ipfs.yt/ipfs/QmXoypizjW3WknFiJnKLwHCnL72vedxjQkDDP1mXWo6uco/wiki/Floghera.html
But this one looks positioned like a Ney
https://m.youtube.com/watch?v=bB6oMPrKYY4
Few videos so I don’t know.
So in short, the question of how it might play, and be played, is quite open…
?