I'm out here having to literally beg my wife to let me take our one year old to go see a dermatologist to help him with all the itchy rashes he's developed on his hands and feet he's literally bleeding from. She's somehow become convinced that Dermatologists will not have our son's best interest in mind and will only prescribe him steroid creams that will be more dangerous than him having open wounds on his hands and feet. 

She insists we see a naturopath, which I'm actually fine with and willing to do, but so far refuses to compromise on seeing a dermatologist and continues to use animal fat products she finds online that don't treat the rash or the itch whatsoever.  The powerlessness I feel to help my own son is suffocating.

Uhh yikes, I'm sorry.

Unsolicited thoughts: in California there are often MDs with naturopath tendencies, so I think in your situation short term I would try to get her buy in to see one of those. 

And/or a couples therapist may help.  This may be about something bigger she needs help with.

This is terrible. I hope you can change her mind or bear the consequences taking him without her