If you argue that a brain cannot be described by computation and there is something supernatural like soul, that's a fine theory, and the only way to disprove it, is to create working general ai.
Why are those the only two options? There's lots of different philosophical positions, particularly when it comes to consciousness.
The suggestion by Penrose that consciousness is connected to quantum state, and so cannot be copied, or computed on any classical turing machine fitting in the universe, is an interesting way to circumvent strange predictions of functionality, but is not very plausible.
And Jaron Lanier from your other comment explicitly suggests to not use approaches like that, because it would weaken vitality argument, when proven wrong.
But that gets into metaphysics, which is notoriously tricky.