You raise a very good question. Unlike C14 dating, where the halflife is independent of environmental conditions, DNA is a chemical molecule, whose decomposition is a chemical reaction, dependent on exposure to time, temperature, pressure, light, and chemistry of the environment.
I was hoping the article would explain why the conditions would be so favorable to make it possible.
Right. There must have been trillions of dinosaurs over the eons. Perhaps some individuals were buried in areas with colder conditions and chemical preserving agents. It may take a long time for us to find out.
