I came to the same conclusion, but still I'd like to research more. Creatine, hair and kidneys don't match very well apparently.
Discussion
"Despite some anecdotal reports and experimental data suggesting that creatine could be deleterious to the kidneys, cumulative evidence from independent, randomized controlled trials clearly show this is not the case."
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10054094/
If you know you have kidney disease, maybe skip creatine. Otherwise, go for it.