Source? I am an emissions researcher, Catalyst coatings have not changed significantly since 1981 and all catalysts that focus on hydrocarbon reduction (Gasoline three-way and Diesel Oxidation Cat) can be poisoned by zinc. It was not a huge issue until vehicles started getting better and surpassing the old 100k and 150k mile durability limits as the zinc introduced to a cat through oil consumption is relatively low even with a high ZDDP%.
Modern anti-wear additives and break-in lubricants are just as good as old high ZDDP oils and lubricants. Additionally, the break-in period for his camshaft even if he used a high ZDDP break-in lube should not be super bad but he will want to change the oil relatively quickly to a standard oil to preserve his cat.