I parse my words the way I do because people like you so often assume that human language is capable of assessing all truth. That would be a mistake to assume.
From my POV, you have stated something logically false with your first sentence there: "If you are going to hold God meticulously determines all things, you cannot logically hold to a position where he is not the cause of all of man's sin". You will notice that in the post you answer, I carefully emphasized the word, "THE", in saying that I don't claim God is THE cause, as though no other thing also caused, each man's sin. It's really pretty simple —God began the chains of causation; other things, effects all, are also causes within the chains of causation.
To you, I suppose, that implies something Deistic, that God only began all things, but Deism, too, is illogical: One science writer observed, rather poetically, something like, "The seeds of all that exists today, were sown in the Big Bang." My point is not to defend that writer nor his notions, but to point at his use of the notion of 'causation'. In that, he was exactly right. Within time, whatever happens is a result of what came before it.
God created. And he did so with intention, and there have been no mistakes, and no "if's", on his part. His creation does not determine his decree. But his creation does exactly as he decreed. If God is omniscient, and omnipotent, he intended EVERY DETAIL of what resulted from his creating.
I do hold that God determines all things, to include man's sin.
There is no such thing as absolute spontaneity of any creature. That is simply illogical.