The plant has been studied and analyzed, with various papers out there, like this one, but there doesn't seem to be anything recognized as effective for people (yet, more studies are probably needed) :
https://www.phcogj.com/sites/default/files/PharmacognJ-13-1-...
In previous studies, it was found that the Akar Kuning (Arcangelisia flava Merr) contains chemical compounds, including saponins, flavonoids and tannins, besides that the roots also contain glycosides and alkaloids, especially the isokuinolin group, namely berberine, jatrorizin, and palmatin. There are also some minor alkaloids such as columbamine dehidrokoridalmin, homoaromolin and talifendin, and fibraleucin terpenes, and fibraurin has several activities such as antifungal, antiasma, antibacterial, anti-tumor, anti-malarial and anti- inflammatory.
This is most probably the main reason. However there is some debate on whether these learned behaviours can be passed across generations.
Here is David Attenborough showing Orangutans washing clothes/using soap/tools/etc. mimicking what they have seen Humans in their environment do - https://www.youtube.com/watch?v=IFACrIx5SZ0
PS: Also checkout the Orangutan Jungle School video i link here - https://news.ycombinator.com/item?id=40244125
As far as wolves, it's still an open question as to how much they "self-domesticated" before humans noticed and started working from the other end. Seeing how human encampments would produce delicious food scraps in refuse (and still do, just ask any black bear!), it stands to reason that some animals would try to cash in on that opportunity. Then you have a selection process whereby the ones that are too skittish would not even bother, and the ones that are too aggressive would be chased away or worse.