Are rear exhaust manifold bolts open to crank case or oil passages?

Are the rear exhaust manifold bolts prone to leak oil? I see smoke coming from under the very end of the exhaust manifold on the passenger side (cyl 8). I haven't seen this before there. I have new rubber valve cover gaskets with steel liner. I had a problem like this on the driver's side, I flattened the surface of the cover around the bolt holes and put permatex ultra-black on it, it stopped smoking after I did that. Now I'm seeing this on the passenger side, I don't think I'm seeing oil leak down from the valve cover, but maybe it's happening now.

I'm just wondering if there's any way that oil gets past the rear manifold bolt holes.