Leave it alone, it'll fall off when it's ripe
The problem of the WT is a spiritual one IMHO. Thus you cannot get through to a JW by reasoning or education alone. Their eyes glaze over and they repeat like robots "one pus one equals zero" even if you show them on a calculator the answer is two. It is the same with biblical truths. You can show them stuff which is plain and simple but they usually revert to their false answers.