Except they're the ones who released the hypothetically sentient AI into the wild. They should be liable for that action too.
And the notion of LLMs controlling safety-critical systems scares the piss out of me. I develop such systems, and LLMs are incapable of providing rigorous proof of the rationale behind their decisions. Therefore, they cannot be validated to provide correct conclusions based on a given data set. Unless and until that changes, they should be banned from anything that affects people's lives, livelihoods or physical well-being.