539-70 is very clear. Wt 607 is a valid interpretation. And that is that.
Isaiah 50:1 is also clear:
50 This is what Jehovah says:“Where is the divorce certificate of your mother, whom I sent away?Or to which of my creditors did I sell you?Look! It was because of your own errors you were sold,And because of your own transgressions your mother was sent away.
In the above quoted scripture, the prophet Isaiah refers to God's covenanted people as a nation, as the mother of you people, God being in a husbandly like covenant with the entire nation. But the scripture also refers to the nation as being sent away at that time before the desolation actually occured, as if it already happened and the nation was already in captivity, before the desolation. Hence this scripture is prophetic, being "sent away" was future but as certain as if it had already occurred. And so, your enterpretation of the verses you cite and the interpretation of others as to when the Bible says events actually happened versus the prophetic language of the Bible. You, yourself admitting to being confused about Isa 50:1
It is well established and accepted that the king of Babylon raided Jerusalem 2x. The first time taking part of the nation captive Ez1:1.
It was to king Zedekiah that the prophet Ezeqiel said: "Remove the turban and lift of the crown..remove even the high one..a ruin I shall make it.... it shall cerainly become no one's" (the throne still having a king as Ezeqiel spoke) The "70 years" was a future event and did not begin with the first raid. But you can believe and interpret what you like, your views not invalidating WT. I respect your views and conclusions about the verses you cite but they do not establish the date of the destruction of the first Temple and of Jerusalem. I have posted a very simple method of extrapolating the date.
The desolation begins after the destruction of Jerusalem, the land rests 70 years, then a remnant is to be restored. Going back in time, Babylon falls and the Jews return; subtract 70 years from the date Jewish feet trample Jerusalem ending its rest and one arrives at circa 607. That is how I see it. And I rest my case.