her history book does show the correct date for the fall of Jerusalem <grin>).
Remember that the Watchtower Society believes they were chosen by Jesus as the Faithful and Discrete Slave in 1919 as a result of Jesus returning in 1914. If the year for the fall of Jerusalem is not 607 BCE then that means that Jesus did not return in 1914. If Jesus did not return in 1914 then the Watchtower Society was not chosen as the Faithful and Discrete Slave in 1919.
ALSO... very important...
The Watchtower Society will try to tell her that they predicted that Jesus would return BEFORE it happened... but this is a lie. In reality back in the lat 1800's they said that Jesus returned in 1874 and that the Great Tribulation would END in 1914... basically the end of the world would be in 1914.
The Watchtower Society did not teach that Jesus returned in 1914 until well into the 1930's.