One of the biggest problems of geology/archeology, is determining what happened BEFORE a proven event. While finding an accurately determined 10,000 year old human bone is certainly strong evidence that a human was there 10,000 years ago, it provides no evidence that humans were absent prior to 10,000 years ago. It is entirely possible that humans were there 50,000 years ago, and simply no evidence of it has yet been found.
Maybe this was the very first archaeologist’s bone collection? And he wanted to be buried with his collection.