I don't buy science that is 90% guess work. That sample can be as little as 1000 years old depending on what activity took place. great pressure happens at such depths, depending on sediment and volcanic, seismic activity, flood water run off etc. it could be a fairly young sample, some Pygmies scraping fungus off his foot with a rock while fishing, tossed it overboard his canoe,
petrified wale poop.
I lost respect for science once they started inventing new dinosaurs each time a two inch bone is found somewhere. I think much of it is made up so a scientist can "name" a new species or get written up in the journals.