I’m mostly with you except for the determinism. Not only do we KNOW that the universe is fundamentally probabilistic and not deterministic, all our technology works extremely hard to combat random errors because small electronics are absolutely not deterministic, they are just engineered to have a low enough randomness so we can counteract it.
But it does. If the universe was deterministic, choice would be impossible because all outcomes would be predetermined.
Quantum randomness may not directly provide free will but it does exclude determinism, which would make free will impossible.