Only have a second to reply, so that's the reason for my shortness!

Kitty was retested - no infection. No bacteria present at all.

Vet never mentioned kidneys even once, which I found really odd.

She has a list of tests you have to do in order. First is the urine culture. I would think next would be a blood panel, but no. She wants to do feline leukemia before anything else, followed by numerous other (expensive) tests before doing anything behavioral. And none of those tests had to do with her kidneys.

She is a very skinny cat - always has been. The vet wanted to check her thyroid because of that, which I was ok with, but she won't do that until she runs through the things on the list before that.

She said to never put the cat in the box. :/

I'm at a loss. I had read so many suggestions online (in articles written by vets) and a lot of her information seems to not match up with that.
2c/3a/3b, Fine/med, Dense, high porous, & normal elas.

Lo-poo - Renpure Keratin, SMR, Giovanni SaS
clarifying - mix Johnson's H2T with low poo
Co-wash - Suave Nats. clar. or coco.
RO - GVPCB, Ion Eff. Care, TN.
LI - SMR, Cure Care, or RO
Seal - MO or Jojoba
DT - + honey, ACV, & EVOO to SM masque & GVPCB
PT - Gelatin!, CNPF
Styling - FSG, AIF, BRHG, LALS/PS, GF curl spray gel, SM Souffle/Smoothie, LOOB
Oils - MO!, EVOO, jojoba, GSO, SM Elixer, EVCO, VO5 Hairdressing