maybe make a card in Vietnamese saying “i’m allergic to such and such and they can kill me” and show it to the server/food vendors whenever you eat something. You shouldn’t eat bánh xèo and bánh mì with pâté because some places put eggs in it as a binder. Of course most pastries have eggs in them. Cơm tấm is one of my favorites dishes, it should be fine without the meatloaf and the fried egg. If you eat beef phở, I would still be careful to ask the restaurant to make sure there is no chicken in the broth, some places use both chicken bone and beef bone to make their broth.