What do you make of this?
Romans 5:18-19 NIV
Consequently, just as one trespass resulted in condemnation for all people,
so also one righteous act resulted in justification and life for all people.
19 For just as through the disobedience of the one man the many were made sinners,
so also through the obedience of the one man the many will be made righteous.
One of the Paul's "hard to understand" places. We have only speculations what he meant.
In any case, if this is the only place that worries you, then Christianity is not in danger, is it? Bible has plenty of places that nobody is certain about.
In the worst case, Paul really literally believed in literal Genesis and Genesis is not literal and therefore Paul was mistaken in these two verses. It does not mean that Christianity is finished just because Paul was not perfect.
Christianity is not a domino where one piece knocks down all other pieces. Christianity has the basics of faith (ecumenical creeds), then another layer of doctrine and another layer of doctrine... but for Christianity to "work", only the core doctrines are needed.