I’m not familiar with detox baths, but in doing a bit of background research, they seem to be a relatively harmless homeopathic bath, but have nothing to do with aiding in a gluten reaction.  I would be wary of any If you have celiac, your body’s response will be one of an auto-immune nature and you can’t really reverse that process.  You just need to ride it out as comfortably as you can.  I try to drink as much water as possible, take walks to increase gut motility, and eat fibrous foods (kale, figs/dates, apples, etc.).  We all react differently in the presence of gluten, so you may have little to no reaction, or one that is more severe.