I think there is an issue here, comparing apples with pears. There are distinct markets, the club rental market, the owner/operator market. Both hinge on knowing the aeroplane. The owner has a distinct advantage. He, to a certain degree, knows what he has done to his aeroplane, (or should do), therefore in the frame of EFATO, he should and could do all he can to mitigate the occurrences. Proper/correct maintenance regimes, proper and diligent walk rounds, adherence to owner SOP.
The renter relies on someone else having done all of the above, and places faith on the rental organisation to have a duty of care. I have seen, and been in, some right buckets, but I had the go/no go decision. I have seen some poor decisions made by owners, and again have invoked my go/no go decision.
Life is chance, therefore, if we could predict when the engine may fail, we would all be very rich. I do not think stats exist of failures in the two categories mentioned above, but I would maintain that pilot error is still the main cause of death, even when the engine quits. We generally do not hear about successful engine failure landings, but we tend to here all about them when they go wrong.