First scripture I implore you to re-read is Jon: 10b-11 “do not receive him into your homes or say a greeting to him. For the one who says a greeting to him is a sharer in his wicked works.”
For context, please go back just a few verses to verse 7: “For many deceivers have gone out into the world, those not acknowledging Jesus Christ as coming in the flesh. This is the deceiver and the antichrist.” Verse 10a reinforces this by saying "If anyone comes to to you and does not bring this teaching, do not receive him into your homes…” This is in reference to those who are KNOWINGLY denying the resurrection of Jesus Christ, or that he came in the flesh.
The second scripture is 1Cor 5:11 “…stop keeping in company with anyone called a brother who is sexually immoral or a greedy person or an idolater or a reviler or a drunkard or an extortioner, not even eating with such a man.” Again, context is very import here. This verse is highlighting a special circumstance that the Corinthian congregation was faced with: Verse one of chapter five refers to the man who is sexually immoral with his father’s wife and living with her. This is the person acting as if they were are brother, carrying on as though they were doing nothing wrong and, ultimately, acting like a hypocrite. And notice - in spite all of that - nowhere does this account instruct not to say a greeting to such a person. It’s simply saying not associate with him as normal because he is doing something very disturbing.
Another detail to take note of: the scripture says, “But now I am writing you to stop keeping company with anyone called a brother--” so when one decides to leave the WT organization, they are no longer considered a “brother” or sister. How can this apply to ones who have disassociated? This scripture has nothing to do with refusing to say a greeting to these people in public or shunning them even in private (refusing contact).
The custom/tradition of disfellowshipping ones and the process of “applying for reinstatement” and undergoing a set period of time of “proving” oneself before contact can be made with family and loved ones is completely foreign to what the Bible teaches. One just has to consider the parable Jesus made about the Prodigal Son. His father saw the son returning from a distance and… subsequently sent three servants to sit with him, test him for repentance and gave him a full twelve months to sit outside the father’s home before even being acknowledged by his family? We both know that’s not how the account went. The father came running, fell upon his son and kissed him tenderly - in SPITE - of not knowing his heart condition. This is the essence of true Christian love, as taught by Christ. It is unconditional.
As for sinners who still wish to belong to the organization, WT offers us this scripture from 2Thes 3:14 “But if anyone is not obedient to our word through this letter keep this one marked and stop associating with him, so that he may become ashamed.” Verse 15 reconciles this with “And yet do NOT consider him an enemy, but CONTINUE ADMONISHING HIM AS A BROTHER.” Contrast this with the coldness of shunning as practiced by the Society with video dramatizations and WT articles urging family to not even answer the phone if their disfellowshipped son/daughter/parent is calling. Remember, the Prodigal Son’s father saw his son from a LONG WAY OFF and didn’t have the indoctrinated reflex to turn his face the other way.