Actually the Jehovah's Witnesses became the one true religion, the year that the Watchtower Society became God's visible organization. Organized to gather as many into the "ark:.
May 23
Whither the tribes go up .... to give thanks unto the name of the Lord.--Psalm 122:4.
Three times each year the tribes of Israel went up to Jerusalem. Their going was not so much to make requests of Jehovah but to proclaim his praises and recount his goodness to them. God has now set Zion as the place where he will accept praise from his faithful ones, and in no other place does he accept praise and service. God?s organization on earth is a part of Zion, which is made up of that faithful company of anointed ones who joyfully obey his commandments to do his will. As surely as God made Jerusalem the place or center of worship, just so surely now he has made his visible organization on earth the place where he accepts the praise and service of his people, his anointed ones associate themselves together in what we call the Society to do the work of Jehovah as he has commanded and thereby proclaim the honor of his name. - 1928 IBSA YEARBOOK