I have had almost that same conversation with my parents. My father SWORE to me that there was archaeological proof that 607 BCE was the correct date for their 1914 calculations...I said Where is it? I'd like to see it.
He responded that the Society said there was, so there must be, adn it was wrong to go looking outside the Society for answers.
The word is brainwashing, folks. plain and simple.
--B.