What are they changing to prevent this from happening in the future? Why was the use of LLMs not disclosed in the original article? Do they host any other articles covertly generated by LLMs?

As far as I can tell, the pulled article had no obvious tells and was caught only because the quotes were entirely made up. Surely it's not the only one, though?

My read is, "Oops someone made a mistake and got caught. That shouldn't have happened. Let's do better in the future." and that's about it.