It will not work.
Jehovah's Witnesses would leave by the thousands if the Watchtower told them that.
Now, if the Watchtower keeps telling them that the reason the end is so close is because of all the earthquakes, tsunamis and other natural disasters that have occurred in the last year and the SONY hacking scandal, the commercial jets going down every week, the unrest between blacks and the police in the U.S. the wildfires in Australia, etc. the Jehovah's Witnesses will be all a twitter because they want to believe God is going to kill every nonJW on earth so they can have their material possessions.
How many times out in Field Service did you see sisters (and some brothers) point out a fine house and say that they wanted to move into it after Armageddon?
Jehovah's Witnesses anticipate God murdering 99.9% of the earth's inhabitants so they can live on paradise earth without having to see Christmas decorations, parades, football games, birthday parties and anything else that gives people pleasure.
Jehovah's Witnesses thrive on bad shit and if the Watchtower tells them that God says the nations have repented they are going to be madder than hell at their god.