I think we need to focus on emotions in this situation. People often say they were hurt by the unjust treatment they received in JCs or at the hand of elders when they were going through tough personal issues.
Trying to convince people the JW teachings are wrong doesn't seem to get anywhere when the mind control has caused brain lockdown. Trying to focus on the sadness, injustice, hurt feelings might get better results. Questions like, do you think that was a Christian/ loving thing to do or say to you?