Although they call that calibration it is a misuse of the term. What you say is not relevant to the issue of radioactive dating. You have a definite age from the time you were born. Again, it has a definite age from when it was completed. The method claims to determine the time since a specific event in the past, such as when a rock solidified, or when it was metamorphosed, or when it was altered. Why is it that the 'dates' agree with each other if they're wrong?
Like everyone else, they were descended from Noah, who built and managed the Ark, and from a people who developed an advanced civilization around the Tower of Babel.
The Aborigines of Australia lost some of their technological know-how—it can happen in a generation if parents do not pass it on to their children.
In other words, the interpretations are model-driven.
These sorts of ideas do not really alter the fundamental problem with isotope dating in that we have to make assumptions about the past and we can never know if those assumptions are valid or not.
Mary White in her "After the Browing" in the chapter "Descent from the Glacial Peak ..." discusses variation in lake levels in central New South Wales as an indicator of rainfall.