I am a witness - to the 1975 fiasco.
My parents were baptized in 1969 and I saw and heard it all with my own eyes and ears. Whatever they now say, the JW org DID promote 1975 as the end. They may not have done it with an outright statement, instead they used phrases like 'in the remaining months ahead', not years, and things like that. I was in attendance at the convention in London where the speaker even said it was okay to max out on credit because you will never have to pay it back. Okay, so the GB may say this was not in the script, but it was said in front of many thousands and there was no retraction or correction whatsoever from the platform (in fact, in all my years as a JW I never once heard a correction or retraction and even when someone said something insane during a PT we still all clapped at the end).
So when a modern JW says it never happened that way - I was there.