I’m with you BigH.
If I performed my job with the same failure rate as BMW my name would be fairly well stained and I wouldn’t find work too easily.
They wash their hands of the labour because they aren’t willing to pay the dealer.
Is it a full engine or just bits replaced? I wouldn’t like the old oil filter housing which prob contains the cooler or the old turbo going back on. Who knows how much swarf is inside them.