Wasn’t Timothy taught by his mother, Eunice and his grandmother, Lois? At least it is inferred here. It seems that the sincere faith was handed down to him maternally. And King Lemuel, in Proverbs 31:1 was taught by his mother. Also, at least twice in Proverbs, the son is told not to forsake the teaching of his mother. If women are forbidden to teach at all then these instances would be contradicting this command.
I think your reading of Titus is wooden and rigid. A godly woman who loves God’s word is truly a blessing and enhancement to her husband in the training up of their children. When she is teaching her children and younger women to love God and obey his word isn’t this a huge help to her husband? And isn’t she fulfilling her role as a ‘helpmeet’? This, coupled with her example of respect and submission toward her husband, will go a long way toward training her children in the way they should go.