That would be true only if the universe was deterministic. It seems to actually be indeterministic (I'm not a physicist, but this seems to be the opinion of most given the success of quantum mechanics). So, you could run the universe from the beginning of time and one time you'd choose 4 and another you'd choose 6; neither would be 'free' choices though for reasons stated earlier.
I'm not sure I agree with the last part of your post. What you were referring to omnipotence, I was referring to being able to make a truly 'free' choice. So, the brain does its computing and sends 'you' (your agency) the choice of Wendy's item 4 or 6 and then 'you' can choose. I think that is incorrect.
So you are subbing “chaos” for “free choice,” as if that’s somehow a less nebulous concept...
“Mr. Sciencism, I’m hungry. Should I choose 4 or 6 from the value menu?”
“Well, I don’t know. You might choose #4. You might choose #6. It just depends if this is a universe where you choose 4 or a universe where you choose 6.”
“Oh. Ok. Any way of predicting that?”
“Well, none so far as we know of. But there probably will be someday.”
“Oh. Why do you say that?”
“Well, that’s just the kind of universe this is.”
“But how do you know that’s the sort of universe this is if you don’t even know if it is the sort of universe where I’m going to pick 4 or 6 from the value menu?”
“Hmm... I’m not sure. But you definitely have no free choice. I know that.”
“How?”
“Atoms! Chemicals! Neurons!”
“So atoms, chemicals and neurons know if I am going to choose 4 or 6?”
“Well, they don’t exactly
know either. They just make the choice.”
“Oh. So atoms, chemicals and neurons have free choice?”
“NO! There is no choice. Nothing chooses.”
“Oh. So how do I know if I am going to order 4 or 6?”
“Well, you just have to wait and see.”
“See what?”
“See what you choose.”
“Oh.”