I understand the reasoning because its exactly the kind of reasoning I used when I first joined this forum... And I mean exactly the same topic with the same question.. But I learned a bit since then.
You are thinking human terms now basically.. If someone knows what you will do in 5 minutes, and its 100% sure.. Then you "will" do that, no matter what you believe you have as a choice, if he "knows" you will jump off a cliff in 5 minutes, you "will" jump off a cliff.
Thats basically it right ?
I'm not going to say that the premise is flawed, because technically it isn't and you make a very splendid point, though the conditions you make this statement in are wrong.
If we're talking about a god, a being with unimaginable power, who is outside of the timeline, who is all powerfull, who created everything. Then he would be the kind of entity that could break that rule.
No I know, it doesn't sound logical at all, but we are talking of an illogical entity in the first place, an entity that created the laws we function in.
So eventhough you make a great point, it doesn't work because you're putting limits on god. If god knows what I'm going to do, then I can't do anything else.. But if god is the one who created time, so that things can be done in a certain order, and god is the one who created free will so to speak. Then he's also able to give you free choice.
It took me years to actually get that, and I reckon it won't suddenly change your mind, but thats what I learned.. Eventhough I don't believe in god