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Do the Church Fathers address this topic? Did St. Thomas Aquinas?

My opinion is expressed below,  so notice the use of modal verbs and the hypothetical "if".

If Adam had refused Eve's request to taste of the forbidden fruit, then Adam, as head of the First Family, could have prayerfully led Eve to repentance as acts of repentance and forgiveness are graces from God.  Then Adam would have fulfilled his role as Priest, Prophet, and King. When the two met Christ on their daily walks in Eden, then Adam could have begged Christ to forgive Eve, and things could have been restored.

But would that initial rebellious sin of Eve have left a weakness that could have been passed onto their offspring? Would Christ as Savior and Redeemer still need to be born to redeem us?

We must also ask: Why was Christ our eternal King and God known as the Incarnate God? He created the world, and appeared as the Incarnate God in His daily walks in the Garden of Eden even before His Incarnation as a New Born Child.

"O Happy Fault that merited such and so great a Redeemer!"

Even St. David the Psalmist begged forgiveness and was forgiven long before the birth of Christ. Psalm 50 is a product of that repentance.

"From the woman came the beginning of sin, and by her we all die." ~ Ecclesiasticus 25:33

Growing up I've always been told that if Eve alone sinned, mankind as a whole would not have fallen.