Theta II got killed the fastest, because Hyundai took the Theta I and switched the port injectors to GDI injectors without changing anything else. They kept the 5W-20 oil specification. In short, soot and fuel dilution took these engines to an early grave. If you use an oil with a HTHS of 3.5 or higher, they will last for a very long time.
Same story with the Lamba II engine, it needs an oil with 3.5 HTHS. It fuel dilutes and generates soot. On a thin fuel economy oil, the soot buildup will shave the rod bearings until there's almost nothing left, and the most eager rod pops out.
The entire story about Hyundai not cleaning the crankshafts properly during manufacturing is made up. Imagine how much bigger the backlash would have been if they told the world the truth: that they specified low viscosity conventional oils (yes, they did) for the North American markets to meet EPA fuel economy claims and to cater to the cheapskate consumer who wouldn't spend any money on a motor oil that carried actual specifications anyway.
You only have to ask yourself this one question: why didn't the rest of the world have the same problems with these two engines? Although the Lamba II engine issues weren't nearly as publicized because Hyundai/KIA put them in fewer vehicles, and some of the issues were addressed by KIA by increasing the sump capacity by an extra quart and moving the oil filter next to the oil pan, and by specifying a 5W-30 oil without a API or HTHS restriction.