I don't know about the witnesses, but the Bible said that it wasn't for us to know the day or hour (I think not knowing the year might be implied.)
In any case one's own individual death is each one's personal Judgement Day, as that is the day when that person can no longer make a record with God one way or the other.
IF there's also going to be an end of this literal world alienated from God, AND a person is standing in good stead with his creator at that time, then he will be OK.
IF that really happens I'm guessing everybody else dies a permanent death (as opposed the the death of the believer which can be reversed via resurrection.)
Winning an argument with a JW shouldn't be the skeptic's reason for posting on this board.
You should be able to handle that on your own.
But, then, a lot of that sci-fi technobabble sounds great until you start a real debate.