Being a Schizophrenic Parent

Hi, I am currently learning more and more on schizophrenia. I have a questions for some of the individuals living with schizophrenia and caregivers of schizophrenia. My daughter's biological father was dx with the illness in 2005. He has not been in her life since she was 2 and she is now 10. She has no clue who he is and according to associates that know him, they say that he is not taking his medications on a regular basis and also doing illegal drugs, arguing with imaginary people. His parents whom he lives with are asking for visitation. (they have not seen her since she was 2 as well) I can not lie, I do  not want this because she has built a very father-daughter relationship with my husband who has raised her since she was 3. We are currently fighting this in court. (Trying to terminate his parental rights and let my husband officially adopt her) Wouldn't it be unsafe for him being a deadbeat dad and a paranoid schizophrenic who does not take his medication and does illegal drugs to be around my daughter who is a stranger to him as he is to her?