A lot of gluten in foods comes from GMO wheat which is grown using chemicals. Maybe it isn't the gluten so much as the chemicals from the wheat that the gluten is from that are causing the problems.
I think this comment in particular is getting downvoted because it doesn't say anything. Every food we eat is genetically modified; we've bred it to produce more over the past thousands of years. And "chemicals" is literally everything you, food, and most of the universe is made of.
"Synthetic pesticides and chemical fertilizers are not allowed, although certain organically approved pesticides may be used under limited conditions. In general, organic foods are also not processed using irradiation, industrial solvents, or synthetic food additives."
I see gluten listed, and I know it's commonly believed by some to be a toxin (I don't hold an opinion fwiw), and otherwise it looks like diet changes.
Glad to hear she's feeling better, though.