It could have been hype, I don’t know. Just because a thing is on Nat Geo does not mean a thing is true.
However, tsunamis created by ocean floor displacement also travel huge distances without losing any significant energy.
They don’t even stop once they have hit land.
The program I saw, which I have looked for on youtube for any highlights but could not find, discussed high speed land slides, which was cliff face breaking off straight down into water, and they also discussed long run out landslides hitting water, where a large mass of land travels downhill and then into water, also displacing a large amount of water greater than the amount of land actually hitting it because of air pulled in behind it.
They gave the impression that whatever land event may have caused Hawaiian fossils to appear on Australian mountains would have been pretty epic, and I think, though I may be mistaken, that they associated it with volcanic activity and island creation.
The date 73,000ya is pretty close to the 74,000ya date for the eruption of Toba leaving a crater 16 x 65 miles. I wonder if these events were somehow connected. Was the earth in a particularly restless mode in that millenia?
Apparently after a major Alaskan earthquake in the 1900s there was a tsunami that ran 1,000 feet high up a fiord.