I don’t think I have missed your point. For the “only one which actually happens” hasn’t happened yet. The outcome which will have happened (after it does) cannot be known in advance, unless it has been predetermined. And that is just the point. The future hasn’t been predetermined. That “one and only” outcome will be caused, at least in part by the free choices people will make, and these choices cannot be known in advance.
We are aware of what you are suggesting. But it isn’t logical. If God knows them in advance, then they are going to occur.
It is true that God knows all things, but the future does not yet exist, and so cannot be known.
There are no logical propositions about the future. A “logical proposition” is a statement which is either true of false.
Suppose it were NOW true that you will raise your hand at exactly noon tomorrow. Then it is impossible for you to keep your hand down at exactly noon tomorrow. Similarly, if it were NOW false that you raise your hand at exactly noon tomorrow, it would be impossible for you to raise your hand at noon tomorrow. Where then, is your free will? And so it would be with all other logical propositions about the future (if there were any).
So what sounds like logical propostions about the future are either statements of intention or prediction.
For example, if I say, “I will go to the city tomorrow”, I am not making a statement about a future action of mine; I am making a statement about my intention. I actually mean, “I intend to go to the city tomorrow.” If I say “It will rain tomorrow” I am making a prediction. Or if I say, “Detroit will win the game”, I am making a prediction.
If God (or anyone else) knows something, then that something he knows can be expressed in a sentence which is either true of false. But sentences about the future are neither true of false NOW. The sentence about you raising your hand at exactly noon tomorrow WILL BECOME either true of false at noon tomorrow when you make your decision either to raise your hand or to keep it down.
In conclusion, since sentences about the future are neither true nor false now, then their truth value cannot be known now. Their truth value is related to the decisions of free-will agents. That is why some of the predictions by God Himself, have sometimes not corresponded to reality. Just one example (there are several more). God said through the prophet Jonah, “Forty days and Nineveh will be overthrown.” This was NOT a conditional prophecy; it was an absolute prophecy. When God looked at the hearts of the Ninevites, it seemed that they would not repent. But they had free will! They DID repent. And so God changed His mind and did not bring about the disaster that He said He would bring.
When God saw what they did, how they turned from their evil way, God relented of the disaster that he had said he would do to them, and he did not do it. (Jonah 3:10 ESV)
Now if God had KNOWN they were going to repent and turn from their evil way and that He wouldn’t bring disaster to them after all, why would He have SAID that He would bring disaster to them in 40 days? God doesn’t lie, does He? The scripture says He cannot lie. The only answer to this problem is that God DIDN’T KNOW they would repent and turn from their evil ways. By reading their minds, it seemed to God that they WOULDN’T repent. Thus the prophecy. But when they DID repent of their own free will, God repented (changed His mind) about bringing disaster to them.