from the point of view of the judge and society, i guess, what matters, ultimately, is whether the arguments presented for a case hold, not where did they come from -- so it shouldn't matter if ChatGPT was the one that came up with the argument if the argument is good.
though one could point out that if one particular method of generating arguments tends to generate arguments that take time to analyse but are often enough pointless, we'd save time by not using them.
so assuming that the report will be analysed on its own merits, really, it was 3M who got scammed here, because they paid $475/hr for a guy that was just prompting ChatGPT. i mean, i don't know much about the subject, but that screenshot of the gas detector with the "what am i looking at here"... wow, it looks like i already know enough to be an expert witness. no wonder these people are so drawn to stuff like positive affirmations, when they do make it by faking it.