No, I can’t prove that DNA can’t survive 80 million years.
Nobody can PROVE that unless they make assumptions, because we can’t prove events over such a long time frame.
It is, according to any reputable scientist, beyond the realm of imaginable circumstances....this is why it’s BIG news.
If everybody though 80 Millions year old DNA was nothing, then there would be no debate or concern about it.
Again, science says you find the simplest explanation (Occams’ Razor).
Just looking at the DNA and the date, the simplest explanation is the date is wrong.
How simple is the explanation that in spite of their best efforts, the sample was contaminated?
Occams’ Razor is a probability thing. It’s not a guarantee of certainty.