Putting aside for the moment that a Large Language Model (LLM) is a predictive statistical model based on and producing from what consisted its training set, answering whether or not any algorithm can solve an NP hard problem first requires a clarification; is a brute force exhaustive search allowed?
If it is, I am unsure if an arbitrary LLM could find a solution due to the dependence on training. If not, I am confident in saying an LLM could not solve arbitrary NP hard problems in P time as that has yet to be proven possible AFAIK.