My allergist himself recognizes that people can have sensitivities while testing negative to such hidden food
allergies. A sensitivity may not cause anaphylaxis, but it can still cause one
to have a reaction.
Other common ingredients in marinara sauces, such as your prepared spaghetti sauces are the preservatives used for such products. I have issues with these myself. I also have to be careful with the alum family, especially onions, which I have always hated myself anyway.