Adam blames Eve at Gen 3:12. If he had admitted his guilt and repented, might God have forgiven him?

So it seems. Many other places in the Bible say God is greatly forgiving; also, however, in many places in both OT and NT, this requires admission of guilt and repentance. So Adam’s sin is greatly compounded by his lack of repentance. Even if he were not culpable for knowingly eating of the tree (see above), he is culpable for this grievous sin. This is even worse because his role is to care for and protect Eve, and to act as head of the family. Instead, he puts her in peril.