You are correct. The welding process was a failure. The cracks reappeared right along side the weld bead. It was better than it was before welding, so I attempted to seal the cracks from the inside by pouring epoxy into the water jacket and standing the head on its corner. It initially worked! But after reopening the coolant passage in the deck surface it showed a leak again. At this point I knew it was a lost cause and decided to use the replacement head I bought from a member here. After $700 worth of machining, it is now ready to be ported and assembled.