Is the husband's saying to his wife, in a state of extreme anger: "You are divorced... you are to me as the back of my mother," considered a third divorce along with dhihar, thus making her unlawful to him, especially since they follow the Maliki school of thought and the husband remembers what he said despite his anger?

Issuing fatwas remotely for such matters is not appropriate. The correct approach is to present them to a Sharia court or to specialists. Generally, a marriage conditioned on divorce is like a temporary marriage (mut'ah), and some scholars consider the contract invalid in such a case. This is also the case when there is an agreement and collusion to divorce before the marriage. Anger does not prevent the occurrence of divorce unless it completely removes one's sanity. If the third divorce (talaq) occurs, the woman becomes irrevocably separated (baynunah kubra), and dhihar does not subsequently apply to her.