God knew with absolute certainty that the forbidden fruit was going to be eaten, he knew with absolute certainty that this would result in the fall, he knew this before he created anything, so why bother with the pre-fall period?
Whether the story of Adam and Eve is a metaphore, or it actually happened the way it is written is irrelevent. The fall happened to show us what we already know in our hearts, that there is something more to life, than just this. Deep down inside we all desire to be in the garden of Eden, and to be with God.
Not to labour the point, but free-will is an irrelevance. You can have free-will, or the illusion of it, but the outcome of any decision you make must be known in advance to an omniscient being. It cannot be any other way. It is not therefore impossible (logically speaking) for that being to stop things happening before they do.
First three words of the bible, "in the begining". God was there before the begining, so He must not be bound time, and the way things happen for Him, are uncromprehensible to us. Just because we do not understand the mechanics of living in a universe not bound by time, does not mean that things cannot be stopped from happening, or that free-will does not exist.
The possibility is that a being, such as God, who could just speak the universe into existance, might be smarter than us. But that does not put him our of reach from us, He created us to be with Him, and be His friend. We are lords of the earth.