JWs teach that John the Baptist would not inherit Kingdom of Heaven. However, there are problems with this teaching.
John’s mother Elizabeth was both barren and too old to conceive. (Luke 1:7) Birth of John was an act of “Holy Spirit.” (Luke 1:15) Then we find Jesus saying: “Among those born of women there has not risen anyone greater than John the Baptist; yet whoever is least in the kingdom of heaven [“kingdom of God,” Luke 7:28] is greater than he.” (Mathew 11:11; Luke 7:28)
Greatness of John the Baptist lies in two factors:
1) He was born from the “Holy Spirit” and hence is of the “woman” of Gen 3:15 which JWs teach as the heavenly organization.
2) Life of John the Baptist was like a sacrificial dying for Jesus because he declared: “He must increase, but I must decrease.” (John 3:30)
In other words, not only by his birth but also by his action (extraordinary humility) greatness of John the Baptist has no match whom Jesus himself described as “more than a prophet.” (Mathew 11:9) After showering such great praises to John it is unlikely that Jesus would make sentence such as “whoever is least in the kingdom of heaven [“kingdom of God,” Luke 7:28] is greater than he” which can be interpreted by JWs as John sharing no heavenly hope, especially because of the fact that there cannot be grades in that Kingdom because rest of the Bible overwhelmingly argues that no one earns the right to inherit that Kingdom because all those who become part of new kingdom are bought with blood of Jesus when their inheritance was death, when they were slaves to sin and death; hence question of their greatness doesn’t even arise.