The high oil level is a potential clue; if the diaphragm in the fuel pressure regulator (FPR) has failed, the leaked fuel is discharged thru the leak line to one of the hoses of the crankcase ventilation system, and thence to the crankcase. A slowly failing FPR diaphragm would leak fuel while still maintaining sufficient pressure for the engine to run. When the diaphragm finally fails completely, the engine stops.