1993 Mercedes Benz 190e chain tensioner

When looking at camshaft, is anything look out of order camfollowers (caps) in order 1, 2, 3, 4, it is possible it was assembeled and bound up with cam cap oiling hole not alighned properly, also ioling tube on top could have poor oiling, check this out, if head is gaulded it has to be replaced., I had a young mechanic working with me one summer and he overlooked a small detail similar and cost me a bit of money, but honesty prevailed found it and was straitend out at no extra cost to a very patient customer that is still one of my favorite, he was very understanding and im still doing all of his work, this young mechanic is now a lead mechanic at dealership, stops by regulary and helps out on weekends, even mechanics are human it might be a oversight.