Changing an Adult's Name: Undo Half an Adoption

My question involves name change laws in the State of: California/Nevada

I was adopted in Nevada but born California. My adopted mom doesn't want me and I've only seen here twice in the last seven years both times because of my adopted dad. My biological mother wanted me just couldn't raise me, she recently passed away and was cremated so no dna testing. I want my bio mom put back on my birth certificate is there a way to do that since adult adoption isn't possible now that she's gone. I do not want my sperm donor on my birth certificate as he was a vile man who tortured me so I don't want to undo my dad's adoption of me. Any suggestions or help would be appreciated.

Thanks,
Arolena

Changing an Adult's Name: Undo Half an Adoption