Is a divorce on the condition of absolution – due to the wife's waiver of her rights and the existence of two previous divorces – considered a khul‘ that is not counted as a divorce, based on the fatwa of Ibn Taymiyyah, thereby allowing the spouses to return to each other?

Divorce based on ibra' (a woman's release of her mahr or other rights in exchange for divorce) is a type of khul'. Khul' is an annulment (faskh), not a divorce (talaq), so it does not count towards the three divorces. The husband may remarry his wife with a new contract. One should be careful not to be lenient in matters of divorce and to solve marital problems with wisdom.