To be fair to Ars Technica, that doesn't sound like the case to me.
The "journalist" in question seems to be suggesting that this was their own bad judgment to use AI to "find relevant quotes" from the source material.
Having said that, there's also a senior editor on the by-line who hasn't been held accountable for clearly failing to do their job, which as I understand it, is to read, edit and verify the contents of the article. So in a way Ars seems to have a problem with quality whether or not the use of AI was mandated.