quote - But how will they explain the features of this prophecy that clearly indicates that the locust plague is brought on because of the wickedness of his people? - end quote
LOL! They won't have too. Whenever speaking about it or writing about it, they will just ignore any negative mention of why the calamity will come upon them and because JW's care more about what is written in an WTS publication than what is in the Bible, they will never connect beforehand that this calamity is brought as punishment.
Look at what they do with Gog's attack. (Gog's attack and Northerner's attack one in the same) All JW's will tell you that they expect a future attack by Gog because the WTS teaches that but you will never hear them say why Jehovah will bring Gog to attack them.
The following is the way the WTS/GB spin Gog's attack.
[Restored
At Last! p. 187-188 - The
nations will “devise an evil plan.” They will seek to vent their long-standing
rage and hatred on Jehovah’s worshippers, who will seem vulnerable, as if
“living in settlements unprotected by walls, bars, or gates.” The nations will
also be eager to “take much spoil and plunder” from those “who are accumulating
wealth.” (Ezek. 38:10-12)…
The nations may try to disrupt our way of life and stop us from carrying out
our worship. To that end, perhaps they will try to interrupt the flow of
spiritual food, prevent us from meeting together, break up the unity we enjoy,
and stop us from zealously proclaiming God’s message.
That is how JW's perceive Gog's coming attack upon them but here is the reason why it will occur:
[Ezekiel 38:15 You will come from your place, from the remotest parts of the north,+ you and many peoples with you, all of them riding on horses, a great assembly, a vast army.+ 16 Like clouds covering the land, you will come against my people Israel. In the final part of the days I will bring you against my land+]
[Ezekiel 39:23 And the nations will have to
know that it was because of their error that
they, the house of Israel, went into exile, on account of the fact that they behaved
unfaithfully toward me, so
that I concealed my face from them and gave them into the hand of their
adversaries, and they kept falling, all of them, by the sword.’ 24 According to their
uncleanness and according to their transgressions I did with them, and I kept concealing my face from them.’]