How certain are we really that not the materials but the resulting figurine is authentic?

From Wikipedia on the Lion-man (English):

> It was not until archaeologist Joachim Hahn started an inventory and assembly of more than 200 fragments that a figurine with animal and human features began to emerge.[5]

We have seen countless examples before, from the Brontosaur skull mixup mess to the heavy-handed "restoration" of the Knossos Palace, including an essential made up King-Priest frieze from real fragments by Sir Arthur Evans.

For some reason the Wikipedia pages don't contain this information on Brontosaur or Evans' pages for example...