Head gasket job gone bad

[sleepertruck72]

Long story... a coworker did a head gasket on a 2007 GMC Yukon Denali. The driver side head had a broken exhaust manifold bolt at the rear of the head. So he did the job and when he fired it up it sounded like a racket. It sounded like something was loose maybe pushrods. He stripped it down and all was good. The pushrods were not oiling. No oil. We squirted some oil down the pushrod guides but it was still loud. We ran the engine for about 10 min. No change in noise. We removed the oil filter and ran the engine, oil pumped just fine. What could be the culprit ? Engine ran just fine prior to head gasket job. I did notice the head gasket was for 4.8 ,5.3,and 6.0. This is a 6.2. The gaskets do not have oiling provisions do they ? Were all sorta stumped...