This was my experience as well. Happy to hear it is working for her.
You may find she will be able to WO wash a couple of times stretching those low-poo washings out a little more. It will depend a little on your water (hard, soft, etc) and how thorough she is - it takes a little more manual effort with WO - but it can work surprisingly well. A year and a half ago I never would have believed my hair oily hair would wash up well with just water. At any rate - I'm glad it's working and I bet it will make a difference with her forehead skin, too.
remember, with all advice or suggestions for your hair, YMMV!!
2b wavy, medium texture, low porosity, med-high density. Protein finicky.
Cleansing: DCNP, every 4-5 days (occasionally use CJ cleansers).
RO: CJSC, occasionally use JCDC
LI: KCKT or CJSL
Gel: KCCC, CJCIAB for 2nd day hair (sometimes third)
Heat is my friend: warm water rinses, steam caps, and diffuse dry. I love CLU cloths and my Denman.