Well....Maybe

[abaris]

The problem with this is that we only find what endures.  Someone could have invented paper 10,000 years ago and written an Encyclopedia but because paper rots in moist climates the chances of finding a remnant are slim to none.

Not very likely. Culture requires organisation. And an organised society is likely to leave behind something enduring. The leaders of said society would want to perpetuate their achievements. So, written in stone or impressive monuments such as Stone Henge are likely to be the real deal. Not to forget the cave paintings of Lascaux or Altamira. Or, especially, since it's very close to home the Venus of Willendorf, discovered in 1908 and estimated to be between 20- and 25.000 years old



Another question entirely is the authenticity of this to be writing. As your article mentions, there's still a debate going on. But, to go back to the Venus of Willendorf. Willendorf is right on the banks of the Danube. So there certainly was a civilization there, reaching back at least 20.000 years.