They found the fossil of a mummified hadrosaur. It's stone. Compare that picture of the mammoth to this photo of the hadrosaur's "skin":
Really not the same thing. Why don't we find dinosaurs that look as preserved and lifelike as that mammoth?
"Dinosaur mummy yields organic molecules
This is the first dinosaur to reveal intact skin structure, expert says"
That of course is before they even start cutting past the skin...
“The existing “skin,” as described in a Proceedings of the Royal Society B paper this week, consists of a mixture of the original cellular components mixed with mineralized material. “