The head probably isn't getting oil because the head gasket was put on wrong. When it is put on wrong, it blocks the oil passage that goes to the top of the head. If that is the case, then the head is likely junk, because it damaged the cam journals and there is no fixing them, since there are no bearings or replaceable parts.
Even if it wasn't a head gasket problem, if the cam didn't get oil, then the head is likely junk, for the above mentioned reasons.