What I am hearing you say is that the transgression of the commandment to not eat from the tree was the cause their being separated from God and not necessarily that they gained a knowledge of good and evil from the experience.
I find it interesting that God, who is an all knowing being and knows the future before it transpires, knew before Adam and Eve ever partook of the fruit that they would partake. God still went through with placing them in this situation because I believe that he wanted and expected the outcome of the fall of mankind. I believe it is critical that mankind go through a mortal fallen state of existence for their progression in God's eternal plan.
It is interesting from a Christian point of view that Jesus was foreordained to be a Savior for mankind before Adam and Eve ever set foot on the earth. The plan of Salvation began in the premortal world of spirits before the creation of the earth. Thus God planned for the fall of man and foreordained a Savior. He thus wanted mankind to gain a knowledge of good and evil and to become more like God himself.
1 Peter 1:20
20 Who verily was foreordained before the foundation of the world, but was manifest in these last times for you,
Revelation 13:8
8 And all that dwell upon the earth shall worship him, whose names are not written in the book of life of the Lamb slain from the foundation of the world.
Ephesians 1:4
4 According as he hath chosen us in him before the foundation of the world, that we should be holy and without blame before him in love:
Certainly if God wanted to avoid the fall of Adam and Eve, given his foreknowledge and power, he could and would have done it. This mortal life is all part of the great plan God has for us even before the foundation of this earth. That we become more like God in gaining a knowledge of good and evil is part of our progression.
