In actuality, it is not necessary to disprove 607 in order to disprove 1914.
The Watch Tower Society has already disproved 1914 in its own published mat eri als.
Suppose that A.D. 1915 should pass with the
world's affairs all serene and with evidence that the
"very elect" had not all been "changed" and without
the restoration of natural Israel to favor under the
New Covenant. (Rom. 11:12,15.) What then?
Would not that prove our chronology wrong? Yes,
surely! And would not that prove a keen
disappointment? Indeed it would! It would work
irreparable wreck to the Parallel dispensations
and Israel's Double, and to the Jubilee calculations,
and to the prophecy of the 2300 days of Daniel, and
to the epoch called "Gentile Times," ...
(Watch Tower, Dec. 15, 1913 Reprints p. 5368)
And what would this 'irreparable wreck to the epoch called "Gentile Times"' mean? Why does the Watch Tower Society so desperately defend their erroneous chronology?
It is not necessary to show how if a change of 19
years were made in the chronology the time from
Jacob to Jesus would become shortened from 1815
to 1826 years, and the entire system of dates based
on the "Jewish parallels" would collapse; how the
jubilee system dates would fall out of place from its
present symmetry: how the 2520-year parallels
would disappear; how the entire system of dates
would be scattered; how there could he no
foundation for faith in the resulting chronological
jumble; and how there could be no sound reason for
believing in the presence of the Lord, the place and
work of Pastor Russell, the end of the age, the
harvest work, or in any of the literature published by
the Society.
(Watch Tower, June 15, 1922 p. 187)