"The ultimate question is whether the doctrine of the goodness of God or that of the inerrancy of Scripture is to prevail when they conflict."
With respect to Mr. Lewis, I believe the better question is whether the doctrine of the goodness of God or that of the literalness of Scripture is to prevail when they conflict.
When as Christians we claim that the Bible is a mix of true and false, of this is from God but not that, we go down a very slippery slope. The obvious question many would have is how in the world then can you claim any of it is true or from God? This one says this part is true or divine another claims something different. It is remindful of when Paul admonished that one says he belongs to Apollos and another says he belongs to Paul but that is Christ divided. One Christian says, the flood is myth, another Joshua did not receive orders from God to kill etc. Yet, that is what the Bible itself is saying. If one part is wrong all parts are wrong.
Many times Jesus used stories to teach a truth. If he is the reflection of his Father and if when we see him we see the Father then it could also be that Jesus taught in a similar fashion to the Father. Does the creation of Adam and Eve in Genesis 2 have to be literal for the religious truths in that story to be understood? No. And as Christians we are free to believe it literal or not literal but the truth of it remains the same and that is what is important. Did the flood actually have to occur in every detail, the burning of Sodom, the parting of the Red Sea, the killing of nations in opposition to God, Jonah in the fish, the Ninevites, and so on. No. They did not have to occur in exact detail in order for the truth of it or the religious lesson of it to be understood. But, again, being free Christians we are free to believe literal or not literal and either way the truth of it remains. Either way we have a true lesson that helps us to understand our Father.
The OT is true and real, its teachings are true and real. We can argue the truth of the flood and the burning of Sodom as from God, whether literal or a lesson in parable form it is still a truth. Jesus never said we could dismiss accounts in the OT merely because they appeared implausible. He taught using implausible stories himself but in those stories were life saving truths. So too with the OT, all of it contains true things, true historical events and as well as true lessons in order that we may learn about our God who is both love and a burning fire as his Son also is.
"His winnowing fork is in his hand to thoroughly clear his threshing floor, and to gather the wheat in his barn; but he will burn up the chaff with unquenchable fire." Luke 3:17