Then Jesus said to his disciples: “Truly I say to you that it will be difficult for a rich man to enter the Kingdom of the heavens. Again I say to you, it is easier for a camel to get through a needle’s eye than for a rich man to enter the Kingdom of God.” (Mathew 19:23, 24, https://www.jw.org/en/library/bible/study-bible/books/matthew/19/) For Jesus both “kingdom of heaven and kingdom of God” are interchangeable—they are one and the same. When earth comes again under God’s rulership, earth becomes a “Kingdom of Heaven.” (Mathew 5:3, 5) “Those poor in spirit” are defined as those having no self-importance or egoless (Mathew 16:24) and “the meek” too are egoless. Both are interchangeable, and their destiny too is the same.
Disobedient ones CANNOT change God Almighty's plan
This is better understood against the larger picture. God warned against fall of Kingdom of God on earth if humans disobey Him. Yet they disobeyed, and Kingdom of heaven was rejected from earth. Yet there are many who do not disobey Him (Genesis 5:24) For their sake, God is “recreating” the heaven on earth again. (Mathew 19:28-30) Just because some people rejected God’s rulership even against the warning of death punishment, God will not change His purpose for this earth: “So my word that goes out of my mouth will be. vIt will not return to me without results, But it will certainly accomplish whatever is my delight, And it will have sure success in what I send it to do.” (Isaiah 55:11) https://www.jw.org/en/library/bible/study-bible/books/isaiah/55/) God going for a new arrangement of heavenly call would mean HE is partial, and disobedient ones could change the plan of God Almighty.
Teaching about heavenly call is one among other things JWs got wrongly. See how they got wrongly the definition of pagan and God’s people. According to God's word a pagan is one who is loving/greeting only those loving/greeting him, ruled by such things as fear, sensuality, ego, greed, alcohol etc (Matthew 5:43–48; Matthew 6:32; 1 Thessalonians 4:5; Galatians 5:19–21; Luke 22:25). (EPH.4.17-19.NIV) (1PE.4.3-4.NIV). This is in the same vein as God's word describes God’s people as “peace-makers, those pure in heart and those circumcised in heart.” (5:9; Psalm 73:1; Romans 2:11, 28, 29; Jeremiah 4:4) Jesus simply praised non-Jews when they displayed theocratic spirit (Mathew 8:10-12; Mathew 22:1-14) and promised he would disown anyone already belonging to him but fails to be theocratic. (Mathew 7:21-23)
How can such people catch the mind of God and Christ when they refuse to greet their former associates, thus identify themselves as pagans?