Treatment not covered bc it’s "disposable"

I’m looking for advice, I’ll try to explain this as well as I can.

I’m in NJ and have Aetna open acess.

I have medically diagnosed lymphedema for which I already did PT and it was fully covered with no copay required.

Lymphedema causes uncontrollable swelling and it’s dangerously progressive. I need compression garments to manage the swelling for which I have a prescription. My insurer has confirmed (in writing) that they are covered. I found a supplier and when they looked at my policy they told me without even running it that they’ve seen this before, patients are told they have coverage but in fact they are not covered because they are considered disposable (huh? Weird right? Lots of medical equipment is disposable?). Since I really need these garments I decided I could pay out of pocket in the event that insurance does deny my claim. Well, I cannot find anything over the counter that fits. I guess I have freakishly small feet and will need to have a custom garment made. Unfortunately, they are crazy expensive and I cannot risk insurance denying them.

If I appealed a denial would I have a claim based on the fact that I was told the garments are covered?
According to their own clinical policy bulletin, they agree that lymphedema is dangerous and progressive- do I stand a chance if I appeal based on the fact that this is the only possible treatment. By denying the garments, they are denying treatment for this disorder, which they agree is progressive. And then, while writing this all out and googling around, I found this:. https://www.aetna.com/cpb/medical/data/1_99/0069.html Am I reading this correctly- they will not cover otc, but they will cover something custom?

Thank you if you’ve read all this! Appreciate any insight.