I think it is foolish to put dates on things like this because men cannot be trusted and are - sadly - LIARS and scam artist who will sell their mothers for money or fame. For everyone make such a claim, you can find another scientist making a counter claim.
The beauty of scientific research is that the data is reported, and is tested by other scientist. It is standard scientific method to date with carbon 14 to get an accurate date, in addition to other methods.