Now forgive me again please, but they are not prophecies in my opinion. Prophecies to me are about direct communication from the almighty to a man or men on the earth revealing His will. Simply applying some random method of study or maths to written words or even to non-christian structures, well that's not prophecy.
The point i am making is that they claim to be prophets, you've asked for some quotes as to whether they claim this, so i have provided them. If they claim to be prophets and they claim to make prophecies which do not get fulfilled then surely you have to ask yourself whether they are God's chosen people.
Notice in Deuteronomy the distinction between prophets and those who foretell dreams, either way if there sign or wonder does not take place notice what it tells you. And certainly there have been many signs from the JW's that haven't taken place and all this under their claim that they are prophets.
"If a prophet, or one who foretells by dreams, appears among you and announces to you a miraculous sign or wonder, and if the sign or wonder of which he has spoken takes place, and he says, 'Let us follow other gods' (gods you have not known) 'and let us worship them,' you must not listen to the words of that prophet or dreamer. The Lord your God is testing you to find out whether you love him with all your heart and with all your soul. It is the Lord your God you must follow, and him you must revere. Keep his commands and obey him; serve him and hold fast to him. That prophet or dreamer must be put to death, because he preached rebellion against the Lord your God, who brought you out of Egypt and redeemed you from the land of slavery; he has tried to turn you from the way the Lord your God commanded you to follow. You must purge the evil from among you" (Deuteronomy 13:1-5 NIV).
"Watch out for false prophets. They come to you in sheep's clothing, but inwardly they are ferocious wolves. By their fruit you will recognize them. Do people pick grapes from thorn bushes, or figs from thistles? Likewise every good tree bears good fruit, but a bad tree bears bad fruit. A good tree cannot bear bad fruit, and a bad tree cannot bear good fruit. Every tree that does not bear good fruit is cut down and thrown into the fire. Thus, by their fruit you will recognize them.
"At that time many will turn away from the faith and will betray and hate each other, and many false prophets will appear and deceive many people. Because of the increase of wickedness, the love of most will grow cold, but he who stands firm to the end will be saved. . . . For false Christs and false prophets will appear and perform great signs and miracles to deceive even the elect –- if that were possible. See, I have told you ahead of time" (Matthew 24:10-13;24 NIV).
"But there were also false prophets among the people, just as there will be false teachers among you. They will secretly introduce destructive heresies, even denying the sovereign Lord who bought them –- bringing swift destruction on themselves. Many will follow their shameful ways and will bring the way of truth into disrepute. In their greed these teachers will exploit you with stories they have made up. Their condemnation has long been hanging over them, and their destruction has not been sleeping" (2 Peter 2:1-3 NIV).
History has shown that JW's have set dates that they claim to have prophesied. Whether or not you belive they prophesied is down to your interpretation of the word prophecy, but the point is they claim to prophesy. On the basis of the above scriptures, along with their WT articles i have quoted you it is up to you to decide whether or not they are God's chosen people, all i have shown you is scripture and their own quotes.
I wish you well in your journey.
Paul