Her behaviour around food if you refuse to supply the sauce suggests you're incorrect about the 'no special needs' thing.
Theres something 'not quite right' there - I have ARFID, food has to be a certain way or I can't eat it, and yep, I'll go hungry for days rather than eat 'wrong' food.
It is also sometimes very difficult to express or figure out what the hell IS wrong with the food - too dry, to crunchy, incorrect ratio between soft and crunchy (theres some hash browns I can't eat if cooked whole and served whole, but if I cut them up part way through cooking, and cook them in small pieces, they're great!).
Let her have the sauce, say nothing about it, save money by buying less prepackaged processed stuff, have a crack at making your own sauces (I couldn't eat salad until we figured out a salad dressing I like we can make at home, now i have a massive salad with every evening meal. My evening meal is quorn thing, salad and potato crispies. And has been every night for six weeks now.)
Making a big deal about it will just make things worse, the more you create stress and drama, the worse shes going to get and as she does seem to be eating a decent range of proper food, that seems pretty bloody silly to risk over some sauce.
Chances are if you say nothing and just provide the sauce, she will get over it in her own time - my safe food lists change from time to time, and I never know why or when!