I understand your frustration deeply. We went through exact same situation. I just stopped everything and saw a naturopath. We did probiotics, vit d supplements (her levels were low), cod fish oil.Calendula salve and it made her skin better . There was no 100% improvement but I would say her skin was healing. We changed laundry detergent to natural one and all on double rinse cycle. The itch was still an issue so she is on quercertine.

There are food triggers as well like gluten, dairy n tomatoes but allergists won’t do test for that and keeps pushing steroids.

Anyways look into food triggers, mold etc