Does a divorce that was issued unconsciously, without knowing what was said before it, take effect, and does helping the other party afterward stop it from taking effect?

If the situation is as you described, then it appears that you are not obligated to divorce in order to help your colleague. Either you uttered the word "divorce" unintentionally, in which case nothing is binding upon you. Or you said, "I will not help him with divorce," without attributing the divorce to your wife, in which case no divorce is binding upon you unless you intended to effect it, and you did not intend to. We advise you to avoid uttering the word "divorce" absolutely.