I am not aware of an air detector for gluten, but Nima Partners sells a device that can detect gluten in minutes in a small sample of a meal or food that you eat. They are also a sponsor here for full disclosure: https://nimanow.com

Here is some more info on this:  

Your approach makes a lot of sense — focusing on balanced meals and being cautious about cross-contamination is smart, especially when you’re traveling or unsure of a kitchen’s gluten-free practices. Many GF foods do lean toward higher sugar or processed ingredients, so prioritizing whole foods (lean protein, fruits, veggies, healthy fats) at meals can help keep energy steady. For snacks that fill you up, look for protein bars with simple ingredients, higher protein, and lower added sugars — reading labels is key on GF bars since “gluten-free” doesn’t always equal healthy. Pairing a salad with a quality protein bar when you’re unsure about a restaurant’s GF safety is a great strategy to avoid symptoms while still feeling nourished. 

I agree, unfortunately a gluten challenge means intentional gut damage and inflammation to those with celiac disease, and taking lots of AN-PEP enzymes could potentially decrease this and skew the results, although I've not seen specific studies on this idea.

I’m really sorry you’re going through this — what you’re describing is, unfortunately, something many long-term celiac patients encounter. A negative blood test after decades gluten-free does not rule out biopsy-proven celiac disease, and it’s frustrating that your documented history isn’t being taken seriously. Being dismissed while you’re dealing with menopause-related changes, neurological concerns, and recovery from a demanding job would exhaust anyone, and it’s understandable that this is affecting your mental health. You deserve care that looks at the full picture, not quick conclusions, and it’s okay to keep advocating for yourself or seek a provider who truly understands complex autoimmune cases. You’re not imagining this, and you’re not alone.