Searcher,
I think the problem is with the question. Since about April of 1989, Jehovah's Witnesses no longer view the "fall" of Babylon the Great as a single, punctiliar event.
In other words, the "downward tumble" of Babylon the Great "started" when "her" hold on "Jehovah's people" was "broken" in 1919; has continued throughout the "time of the end" and will culminate with "her" final destruction.
Your quote from the May 1, 1989 issue of The Watchtower, which was made after this "adjustment" omits the qualifier, "...in relation to Jehovah's Witnesses." Your other two quotes are older.