Bart,
Not 'disproved' per se, but serious doubt can be cast on the Org's skewed interpretation of certain scriptures. wizzstick has already mentioned a good one - Jer. 25:12.
Jer. 29:10 is another. How could Jehovah say the exiles would be there 'at' Babylon when a) the exiles He was addressing were taken 10 years before Jerusalem was destroyed (so these exiles would, in fact, have been 'at' Babylon 80 years, not 70), and b) Jerusalem may never have been destroyed and further exiles taken if Zedekiah and the people had obeyed Jehovah's instructions (Jer. 27:11,12,17)? Why start the '70 years clock' at an indeterminate time in those exiles' future - a future that was not set? Why mislead those exiles by saying they would only be there 70 years when God really meant 80?
If the 70 years 'desolation, without an inhabitant' period could only start to be counted after Gedaliah's murder in the 7th month of '607,' why did Jehovah tell Ezekiel to prophesy to the 'inhabitants of these ruins' in the 10th month (Ezek. 33:21-29)?
Also, going back to Jer. 29, the Bible says the 70 years would be fulfilled, then the exiles would pray, then Jehovah would bring them back home. Daniel (ch. 9) discerned the 70 years were up and then entreated God for His forgiveness, to turn away His reproach and bless Jerusalem and its sanctuary. If the 70 years finished once the Jews were back home (thereby evidence of God's forgiveness and blessing), why then entreat Him for his forgiveness and blessing?
Just having 539 BCE as the end point of Babylon's 70 years, of the exiles' servitude to Babylon, of Babylon's king being called to account, will screw up the WTS's 607-based timeline.