[Sopater]

Note that the sample was demineralized. In short, and as the article repeatedly says, these are fossils and the time scale is geologic.

The "bone" was demineralized, not the soft tissue.

It’s not proof of 4,000 year old dinosaurs.

Nor is it proof of 75-million year old dinosaurs. In fact, it strikes a blow against it.

[JimSEA]

The mineralization was what preserved the soft tissue. The minerals were latticed around the soft material and had to be removed before the material was again soft. Nothing in the article questions or brings any uncertainty to the age of the fossil. This creature must have been fossilized very quickly and not left laying around. This would be similar to the fossils that preserve skin impressions and indications of feathers and internal organs. The article is pretty complete.