I have a similar situation involving my grandmother’s father and her mother’s birth parents. I was able to solve both parental mysteries within an hour of receiving my results, but I also have two documents that noted names; one I wasn’t sure about, a newspaper article from 1899 noting the adoption of my great grandmother w/name of birth mother. Also when she gave birth to my grandmother in 1920 (out of wedlock, and she kept her but left the state to give birth), she noted the name of the father. Over the years I had researched these to death to the point I decided to do dna to see if I could get an answer
I note the birth parents, and the two supporting documents (along with dna) to place the people in time. I’ve tried to reach out to relatives of my great grandmothers parents since she had three full siblings (and an older brother at the time of adoption) just to find out if there were any stories of her adoption, but I haven’t had any response to date.
As a mom of adoptees, I’ve kept everything for my sons as I want them to know everything (good, bad, etc). I actually went through a bit of anger after realizing my ggrandma had an older brother and full siblings (and they were married). But she had wonderful adoptive parents.
I think noting this is also good for your descendants and extended family.