I agree with the lube. It seems to me that the center cam journal was dry. If you can post a pic I can tell you if it can be fixed.
If its grooved at all then I would say the head is done. Its not worth it. Also the rocker arm assy adjusters were worn down ? If this is the case then the head wasnt getting oil at all.
Hate to say it but it sounds like the oil feed from block was plugged. Your gonna have to take the head in and have it checked out again. Also your gonna need to flush the block to clean all the oil ports.
I have never seen a head get little to no oil like this. Almost makes me think your oil pump pressure was weak. The only way this happens is if the pressure relief is bad and was stuck open.
I guess basically the whole engine needs to be gone thru. A lot of damage can happen if there is low oil pressure.
