What mechanism are you imagining that would allow a LLM built of neurons to describe what it's like to be made of neurons, when a LLM built of GPUs cannot describe what it's like to be organised sand? The LLM in the GPU cluster is evaluated by performing the same calculations that could be performed by intricate clockwork, or very very slowly by generations of monks using pencil and paper. Just as the monks have thoughts and feelings, it is conceivable (though perhaps impossible) that the brain tissue implementing a LLM has conscious experience; but if so, that experience would not be reflected in the LLM's output.