Jeffro
hahahahaha. Aside from issues with the grammar, the NWT rendering and interpretation is completely illogical in reference to the context of the passage. After Babylon's 70 years are ended, attention is given to the Jews' return. It is completely irrational to insist that attention is given to their return after they're already returned. You really are a lost cause.
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No lack of logic for the context most certainly favors a locative meaning as 'at' or 'in Babylon' rather than 'for Babylon'. But scholar can work with either as it is a matter of opinion because the Hebrew preposition has a wide range of meaning. Jeremiah's words recorded in ch. 29 simply indicated the length of their Exile or period of servitude in Babylon.
scholar JW