Hi. English is not your first language is it? Curious as to where in the world you are?
Anyway, your crankshaft issue doesn't make much sense to me. So let me see if I have this right. Crank was drilled to specs for a pilot bushing hole. There appears to be a "pinhole" at the bottom of the pilot hole. Pressurizing the oiling system (with a drill) results in oil leaking from the pilot hole pinhole. Sorry, but it doesn't make any sense to me. There shouldn't be anything forward of the pilot hole other than solid steel. The oil passage from the #5 main bearing angles forward to the #8 rod journal and it is well forward of the pilot hole. Just look at the pic, you can see how far away the oil feed is from the where the pilot hole is.
Just to clarify, cast cranks are not "porous" because they are cast vs being forged. For some reason, there seems to be a perception that cast cranks are made of cast-iron while forged cranks are made of steel - which is wrong as they are both made of the same material - high strength steel.
How oil would be coming out of this pinhole in the pilot hole just doesn't make any sense to me unless there is something seriously wrong with your crank. By "wrong, I mean either your crank has a serious casting flaw or your pilot hole was drilled way beyond specs to the point where it contacted the feed to the #8 rod journal. If oil is in deed coming out of the pinhole in the pilot hole, your crank has serious issues and I would pull it out and have it carefully inspected by a competent machinist.