One could also see this article as pointing out that these uncured meats are actually cured, but simply using an unapproved curing agent, and thus must by law b

One could also see this article as pointing out that these uncured meats are actually cured, but simply using an unapproved curing agent, and thus must by law be misleadingly labeled as uncured, and must be misleadingly labeled as no nitrates added (despite nitrates indisputably being added). The food still has nitrates and nitrites. Your focus is on the "no safer" part of the headline, which does seem overstated. From basic chemistry, nitrates and nitrites are all salts that dissolve in water. So the only differences between different nitrates are what which cation is present, since the body is designed to deal with sodium ions. I suppose celery based curing agents could potentially have different cations. It is also possible that the amounts introduces are meaningfully different. (And of course, the nitrite side of things differs in a similar manner.) But other than cations, and amount of nitrate and nitrite salts remaining in the food, the only other plausible difference is any trace impurities in the curing agent which may be related to how the curing agent is sourced.