The first single-celled organisms on Earth did not appear until about a billion years later.
"It can get us to within 20, 50, 100 years or so of dating accuracy." On the scale of the universe, 20, 50 or even 100 years is, for all intents and purposes, nothing. Our galaxy, the Milky Way, is slightly younger, at 13.2 billion years old.
The Earth and our moon are both more than four-and-a-half billion years old.
Fifty, 20, or 100 years is a lot of time, wherein a lot can happen.
Fifty years is the difference between Alexander Graham Bell's telephone and television.
He noticed that trees across the same region, in the same climate, develop rings in the same patterns.