Regrettable Engine strip down !!!! I think " Follow up". But it's not over.

Pretty sure what you're looking at here is oil that was sitting on the top ring and as you rolled the pistons down, that oil slid down the cylinder walls. If you wiped down the cylinder walls and rolled the pistons through, the cylinder walls would be oil free. (should be anyways.)
Oil in the airbox can only come from oil vapors that condensed in the airbox from the PCV system. That much vapor coming from the PCV is generated by blowby around the piston rings. But again, you're compression numbers tell a completely different story. I'm at a loss.

Hi Kawboy,  I have wiped the bore's and every time the pistons go up and down its like a oil pump. Particularly on #1-2-6

Wierd. Only one thing left  to do. Pull the cylinder block and take it from there.  Can't wait to here what you find.

I've been thinking this thru and am also coming-up "blank".

I do have a thought about trying to prove more definitively as to from where specifically and how, that oil is getting to your piston tops.   If you are getting oil  simply by turning the engine over by hand then Pressurize the oil system with air; starting from "0" P.S.I.  and gradually increasing to a few lbs, using a regulator.  The "boost"  might better prove the source(s)