The woman had to separate from her husband till such time that they marry in the Catholic Church, or remain divorced. Divorce, by the way is not a sin; fornication is.
They could have been married in the Catholic Church while the husband was Protestant on a dispensation from the bishop, almost always available. That she did not do that puts her in a state of sin, which she cannot be absolved from while living with the man.
The priest and the RCC and take it and put it somewhere. She's legally married, she is not in a state of sin. Separating from her husband, which goes against clear Scriptural command would be sin.
And you claim divorce is not a sin? Pray tell, show us where in the CCC it says that. Then why annulments?
1 Corinthians 7:3-5 The husband should give to his wife her conjugal rights, and likewise the wife to her husband. For the wife does not have authority over her own body, but the husband does. Likewise the husband does not have authority over his own body, but the wife does. Do not deprive one another, except perhaps by agreement for a limited time, that you may devote yourselves to prayer; but then come together again, so that Satan may not tempt you because of your lack of self-control.
1 Corinthians 7:10-16 To the married I give this charge (not I, but the Lord):the wife should not separate from her husband (but if she does, she should remain unmarried or else be reconciled to her husband), and the husband should not divorce his wife.
To the rest I say (I, not the Lord) that if any brother has a wife who is an unbeliever, and she consents to live with him, he should not divorce her. If any woman has a husband who is an unbeliever, and he consents to live with her, she should not divorce him. For the unbelieving husband is made holy because of his wife, and the unbelieving wife is made holy because of her husband. Otherwise your children would be unclean, but as it is, they are holy. But if the unbelieving partner separates, let it be so. In such cases the brother or sister is not enslaved. God has called you to peace. For how do you know, wife, whether you will save your husband? Or how do you know, husband, whether you will save your wife?
Why do you teach things contrary to Scripture? Why does the Catholic church teach things contrary to Scripture?
That's forcing people to sin. Real sin. Not the made up stuff the Catholic church has called sin.
Is THIS a yes or a no?