Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
We do not know the reality of the product you are asking about. But the principle about this food is that it is permissible (Halal) to eat, and we cannot say it is Haram just by doubt. A Muslim is not required to investigate its ingredients. It is enough for him to check what is written on it.
If these letters are sent by trustworthy people, and they have a proof about their claim that it contains pork, then you have to take that advice, but if it is only a question of doubt and fears then you do not have to.
Anyway, a Muslim has to be cautious, but he cannot oblige others to act accordingly.
There is a Hadith reported by Ahmad "Leave what you doubt about, and take what you do not doubt about meaning (when in doubt, avoid it)."
Allah knows best.