Are a couple who were not legally married, and sufficed with a Sharia judge's decision to affirm their marriage with a backdated entry based on false information, considered legally married during the period between the court's decision and the correct legal marriage contract? And are they sinful for what transpired between them in terms of words?

A "fictive marriage" (or sham marriage) is not considered a valid Islamic marriage because it lacks the fundamental conditions, such as the guardian (wali), witnesses, and offer and acceptance (ijab wa qabul). Consequently, the rulings of a valid marriage do not apply to it. This includes: the husband's divorce of this woman is not effective, because divorce only applies to a wife, and she is not one. There is no sin upon the man for telling her: "You are not suitable for me, and I do not want you as a wife," unless this statement is accompanied by insults or verbal abuse.