Its like a hurricane in there while the engine is running . With oil instead of rain .... I am sure the chain gets ample oil with or without a hole in the bolt .
Where does the oil come from if you don’t get it there? Like AJ said, oil moves downhill, and under acceleration the oil moves to the rear.
I’ve seen enough worn out timing sets, fuel pump eccentrics and junked gear drives to know there is very little actual oil in there. There is a mist, but that doesn’t do much.
