I mean, there's an OLM, it tells you when to change the oil. The alerts are VERY obvious. There's no way to formulate an excuse that works that out of the picture here.
From reading the article, he had an independent shop (instant oil change place?) tell him he could go 24,000km on the oil. If that's true, and he has evidence of that, that's who should be footing the bill for the engine replacement. It isn't FCA/Stellantis's problem that somebody got hoodwinked by some fly by night operation employing a crack team of rapscallions peddling mad mythos about oil drain intervals for vehicles under warranty, the terms of which this clearly violates.