I think it's interesting that conspiracy theory tropes seem to recur very reliably over time. I have an interest in this topic and when I'm reading about it, I find there's a lot of rhyming.
Conspiracism and exploded scientific hypothesis are quite different in nature. They're "wrong" in quite different ways. I recently made a comment addressing this and it might interest you:
https://news.ycombinator.com/item?id=34186172
To your last point, origin myths are a claim about religious truth, not scientific truth. You can't meaningfully compare statements from different epistemologies like that.
So how would they be left IN? Would the archeological community say to them, respectfully, "Our evidence is that First Peoples arrived from Siberia somewhere between 20,000 - 10,000 BCE. What do you think?"
So what would their reaction be? Would it be:
1) We don't know; our myths don't go back that far; you tell US, or
2) You are a colonialist to even talk about this.
??
Has that in fact happened?
> we've lost their trust & aren't entitled to the pieces of the puzzle they may have
That would be unfortunate, but if you're an anthropologist who'd like to solve the puzzle, what should you do?
Certainly. I've heard of some native archaeologists, but I'll confess I'm not super up on the topic.
> If you're an anthropologist who'd like to solve the puzzle, what should you do?
Well, if you're an anthropologist, and some group of people makes it very clear they aren't a puzzle & won't be studied (say, the people of Sentinel Island) - go do something else maybe? Curiosity doesn't entitle you to answers, there's plenty of other stuff for an anthropologist to do. I feel like the first rule of anthropology is, "respect the culture you're studying and take it seriously," and if what they're telling you is "mind your business" - well, listen.
Returning to Sentinel Island, we might not know why they don't want to talk to us, but they've made it abundantly clear that the lines of communication are closed. Surely we could spy on them from satellites, drop surveillance devices from helicopters, et cetera, and start to understand their culture that way. For that matter, we could create some sort of arrow-proof vehicle and overpower their efforts to repel us. But why should be? Just because we're curious about them? Why should we privilege our curiosity over their clear desire to be left alone?
And if they are interested in sharing their oral tradition with you, and you sneer at it - well, they might rescind your invitation.
In any case, what constitutes "sneering" at their oral tradition? As you said, science & religion are not the same. So what should a scientist do if their beliefs differ from science's?
Sneering would be something like saying, and I mean this with all due respect, "you didn't come out of the ground in that canyon, we all came from Africa" - misconstruing what they're saying, seeking to correct rather than understand, generally being rude and dismissive. If someone shares something with you, it's up to you to figure out how and whether to incorporate it into your epistemology; if you're having trouble with that, it might be tempting to say, "the problem is that your epistemology sucks," but a.) That's an indecent way to treat someone and b.) No one is going to learn anything that way and c.) The problem is actually that you gave up on trying to understand, not that there was no resolution to the conundrum, and not that their epistemology is "inferior" in some way.
Consider that when a native culture has an origin story involving a specific place, regardless of whether we have believe that humanity evolved there, there is really no reason to doubt their culture emerged there and that that place has an important bearing in their.
I'm pretty sure that's what I would do.
These results decreased belief in an aether (though more complex experiments were needed to falsify the possibility that the Earth was dragging aether with it). Additionally, a series of length / time dilations were proposed for moving objects to explain the bizarre fact that the speed of the any light was measured the same regardless of the relative movement of the measuring observer. At this point Einstein stepped in and explained the theory of Special Relativity and how speeds don't add linearly and distances and times don't transform as one would naively expect under Galilean relativity. It was a really a generalization of the previously proposed Lorentz transformations that returned to the idea that all movement was relative. The spacetime that transforms in this way is called "Minkowskian".
Eventually after this, Quantum Mechanics developed into Quantum Field Theory, which is inherently relativistic and embedded in Minkowskian spacetime. In this view, electromagnetic photons are just excitations of the quantum field. Things basically came full circle and the quantum field is essentially an aether as envisioned all along. The difference is that it is relativistic / Minkowskian, and as such doesn't have a particular reference frame in which it is "not moving".
Note that even before the development fo QFT, this is what Einstein was saying: "More careful reflection teaches us however, that the special theory of relativity does not compel us to deny ether. We may assume the existence of an ether; only we must give up ascribing a definite state of motion to it, i.e. we must by abstraction take from it the last mechanical characteristic which Lorentz had still left it. We shall see later that this point of view, the conceivability of which I shall at once endeavour to make more intelligible by a somewhat halting comparison, is justified by the results of the general theory of relativity."
Einstein's whole letter is a great read: https://mathshistory.st-andrews.ac.uk/Extras/Einstein_ether/
The fact that the 19th century featured provably wrong theories about where the native peoples came from is not suggestive of anything. They thought there was an ether that light traveled through, too.
Native peoples' myths are often "we were always here; we sprang from the earth." Well, we all came from Africa, ultimately.