Does a divorce in absence count for the wife, and prevent reconciliation, if witnesses are brought in without her knowledge or her hearing the pronouncement of divorce?

For a divorce to occur, the presence of the wife, her hearing of it, or the presence of witnesses is not a condition. Thus, if the husband utters the divorce in her absence, it takes effect. The same applies if he writes it with the intention of divorce. If he uttered the divorce for the first time, it occurred, and your sending of the divorce paper via WhatsApp is merely notification, not a second divorce. The second divorce, pronounced in her hearing and before witnesses, is valid, as is the third divorce pronounced before witnesses in her absence. Therefore, she has become irrevocably divorced from you (baynunah kubra), and she is not lawful for you until she marries another husband in a marriage of genuine desire, not merely for the purpose of making her lawful again (tahlil). Allah Almighty said: ﴿And if he has divorced her [for the third time], then she is not lawful to him afterward until she marries another husband.﴾ And, "Allah cursed the one who makes a woman lawful for her previous husband and the one for whom she is made lawful."