@kisianik Welcome to Mayo Connect! As a nurse you find it so disconcerting to be in this situation with your mother. You can contact Mayo Clinic at http://mayocl.in/1mtmR63
Here is what Mayo Clinic has to say about nephrotic syndrome: https://www.mayoclinic.org/diseases-conditions/nephrotic-syndrome/symptoms-causes/syc-20375608
From the American Kidney Fund, comes this website: https://www.kidneyfund.org/kidney-disease/other-kidney-conditions/rare-diseases/nephrotic-syndrome/

I know from experience that it is critical to find out the cause of protein shedding in the kidneys. I am stage 4 kidney disease, due to a rare disease that deposits collagen into the glomeruli components of my kidneys. Other causes could be diabetes or systemic lupus.

You didn't mention where her primary diagnosis came from. Besides UCLA, Cedars Sinai and Keck School of Medicine at USC are good west coast sources for you. Those last two were who diagnosed my ultra-rare disease.
I hope you let me know what you find out, We are all patients/family members/caregivers here, who share their own experience and strength with others.
Ginger