93 e32 m60 - Nikasil or something else?

Bought a 93 E32 M60. No warning lights on. Had a oil change performed when I took possession of vehicle. After a few months I took it back to the same service shop for a top off. The new hire didn't even know how to open the hood! I thought nothing of it but laughed. He finished the top off and i left.

40-50 miles away from the shop on the highway, car lunges then stalls out. Subsequently I changed the MAF sensor and fuel pump. When i tried to start the car it cranks but there is this loud rattle/banging sound coming from what seems to be the right head. Is it possible this kid filled my engine block with something other than oil?!

And after 19 years on the road is it possible for the Nikasil issue to still be a factor? And if so, anyone have any idea of the repair cost?

Nikasil won't be an issue after 19 years. Maybe he overfilled the oil - can cause serious damage if that happened.

And that's what I was originally thinking! But the dipstick said it was at level.