> If you need two things to happen at the same time in sync with each other no matter if they are separated by billions of miles, then you need faster-than-light travel, or some magic [1]; see what I did there?

No. Because even if you had solid evidence for the hypothesis that quantum mechanical effects are indispensable in making our brains work (which we don't), then that is still not preventing simulation. You need some uncomputable component, which physics right now neither provides nor predicts.

And fleeing into "we don't know 100% of physics yet" is a bad hypothesis, because we can make very accurate physical predictions already-- you would need our brains to "amplify" some very small gap in our physical understanding, and this does not match with how "robust" the operation of our brain is-- amplifiers, by their very nature, are highly sensitive to disruption or disturbances, but a human can stay conscious even with a particle accelerator firing through his brain.