Secular researchers described dozens of them over the years, from mummified skin and dried red blood to still-purple retinas, and they assign them ages of tens of millions of years."
Here is a 2008 book which discusses all of those "dozens of them", as of 2008.
First, you will find that most "soft tissue" found are, in fact, well preserved stone fossils, not organic material:
So, the cases of actual preserved soft organic tissues found from the age of dinosaurs are, in fact, very small, and all controversial.
And so we're clear: there are no dino-DNA fragments found.
Second, what is claimed, though not yet fully accepted, is dino-collegen, simple organic matter, mentioned briefly here.
These finds, if fully confirmed, demonstrate that under ideal conditions some organic material can survive a very long time indeed.
They certainly do not "prove" that every other method and idea about the earth's age is suddenly wrong.
from the article: "However, the science of tissue decay clearly does not permit these long ages."
Rubbish.