You certainly have taken a positive approach to resolving your sinus problems.
However, and sadly, allergy tests are not definitive and are often faulty.
I can't say that I notice certain foods, drinks or chemicals that make it worse. It's really there all the time.
Sadly, so are allergens and irritants.
I was hoping that food allergies was causing the problem but I have eliminated the foods which I am sensitive to.
There are many allergens and irritants that could cause both nasty sinus problems and breathing problems.
You can't do much to avoid outside pollens, such as tree, weed and grass pollens. I had very mild locally tailored tree, grass and weed pollen allergy shots for a while and they seemed to help.
Since it can take anywhere from one to ten different allergens to cause uncomfortable sinus or breathing problems, the task of avoiding ALL of the different allergens can be very difficult.
I had different types of allergy tests. In my case, I was allergic to everything and suffered for many years with nasty, clogged up, painful sinuses. I also took "specific" allergy shots for years, which were strengthened each week.
I tried Acupuncture. I even bought my own Acupuncture stimulator and tried self stimulation.
I finally got my sinus allergies under control by eating the best quality, home made foods I could eat, and by avoiding all kinds of drinks, alcohol, chemicals, some plastics, processed meats, gravies, some soups, dairy products, vegetable gums, animals, rugs, cloth furniture, smelly wooden cabinets, some metals, cigarette smoke (direct or second hand or even in someone's clothes or hair, various odors, and by taking Fluticasone nasal spray. Sadly, I've had to stop getting takeouts or even eating out at restaurants.
As I continued to eliminate foods from my diet, and home chemicals, etc., my sinus problems continued to get better, until finally I no longer had or have any problems with my sinuses. Except, I have to take one snort of Fluticasone in each nostril, once a day.
I am not suggesting that you go to the extremes that I have had to go to, but you might consider living a bubble life, like mine, for a week or two, to see if it helps; and then if it does, slowly adding things back into your "bubble", like takeouts, etc., until the sinus problems come back.
Mind you, I am not a health professional, nor do I have any medical training or education, so you may consider these the words of some crazed fool and disregard my post!
Take care, and best of luck solving your nasty sinus problems!