Yes, ammonia forms in different situations that triggers nitrogen. The turning of chlorophyll in leaf that has had an incomplete cure is the most common in tobaccos, especially flu cured which is a rushed curing process. Usually it has off gassed, but in some it hasn't had the chance. I think cigar leaf color curing is also very prone, which is very similar to how reds are formed.
Ammonia can also come from being triggered by exposure to acids, especially if the tobacco is very freshly flu cured. This is why I've never heard of it being detected in MacBarens ODF, because that fire cure process really wrings the tobacco out, in my estimation. It is cured completely black.
Ultimately, I think that Mike and Mary were geniuses. Their's was always my favorite tobacco. But, to send people to Sutliff's version is like... all of the wine in the world is gone, and someone wants to know what wine tastes like, so you pour them a glass of MD2020 and tell them, this is exactly what wine used to taste like.
I've felt a little like Mrlowercase, "This is not WarHorse bar!!" With everyone telling me, "settle down, we know we know, but it is WarHorse Bar." Ha ha.