Does a divorce issued by the husband with the words to his wife: "If you go to your mother, you are divorced," take effect if he intended to threaten and warn, and does not specifically remember the exact wording he used?

If a husband and wife disagree about the occurrence of divorce, the husband's word is to be taken, unless the wife has clear proof, as the default is the continuation of the marital bond.

If the husband is not certain about the wording of the contingent divorce, then no divorce is binding on him, nor is an expiation for an oath required.

As for the wife: if she is certain about the contingency of the divorce and the occurrence of the breach, and it was a first or second divorce, she is not permitted to refuse obedience to her husband, as she returns to his marital bond through reconciliation (raj'ah). However, if it completes the three divorces, then she must seek release from her husband through whatever she can, and she is not permitted to allow him access to herself. She may flee from his house, and she may not marry another man except after seeking release or a ruling of divorce, because outwardly she remains under his marital bond.