That's pretty neat, but not even close to the scale of the extreme rigor of these Indigenous Australian oral traditions. 170 years is basically just two or three generations of elders; no one alive now was around back then, but the elderly bard recounting his tale to his people probably had a grandparent that was there to witness the events, or at least hear of them as they were happening. Therefore, the story would only need to be passed along a few times before it's present incarnation. In a game of telephone, which this can be compared to, the original phrase is usually mostly intact after being passed along to only two or three people.

To pass down a story from 7000 years ago, however, it would need to be told at least a hundred times, though probably many times more. That opens up a lot of opportunity for certain storytellers to add elements, and others to forget certain details, and yet more to slip up on certain figures or change names; the end result may be nothing like what actually happened in reality that inspired it. On this sort of timescale, it is also very possible for a story to simply stop being told, and thus be completely forgotten to posterity.

The example that you posted was cool, but not particularly unique. The article above tells of an oral storytelling tradition that has proved impeccably, perhaps uniquely, accurate even after millenia.