You only have one-third of the story for you have forgotten the 70 years of Exile and the land desolate for the Exilic period.
There is no requirement from Jer 25 for the seventy years to equate to that of exile and desolation; actually quite the opposite, as it's applied explicitly to many nations, and applied to the time of Jer 25 before the last exile. 2 Chron doesn't require it, nor does Daniel.
This has been covered ad nauseum - a plain grammatical reading of the scriptures fits perfectly fine with secular history. The WT's version of events is another story...