A bunch of great info. It is appreciated.
The hydrocortizone cream recommended by rw622 might be something she could try, since it does stop itching. I don’t know if she would risk trying an ear-mold, until she could find out if she had a reaction to the material, if that is her problem. The gold one might appeal to her though. 
Hydrocortisone cream does stop itching, but it is a steroid that can carry side effects as well particularly when used long-term, so you’d have to discuss that with a doctor or at least be aware of the possibility. Steroids don’t always work well for daily, long-term use. It might be fine. You’d just have to check on it.
I understand about not wanting to invest $100-200 in ear molds if she could react to them, and to be fair, there are a few people who react to multiple materials and have trouble finding anything that works for them, however, most people can find something that they do not react to. And with my audiologist, remember, the ear mold company allowed as many changes as needed–in other words, they would remake the molds as needed from different material, until we had a good fit and no reaction–for a length of time which I think was the first 90 days, at no extra charge. That first fee covered everything. So it’s something to consider, if her audiologist offers something similar.