Sounds like theybe improved their QC a bit Since my last time taking a car to them in 1998 or so, when they forgot to re-install the drain plug on my 1987 Maxima (the engine survived, believe it or not, despite being driven for approx. 4 mi with zero oil (I had, however, used Slick 50 and Prolong in it with my Mobil 1 during several OCIs - don’t hold it against me too badly - I was 18 yrs old and a lot of people used those additives back then).
That sucker cranked right up and quit knocking as soon as the crankcase was refilled!