Any real estate lawyer?

My dad is having a problem purchasing a home, him and the ex wife been separated for 4yrs now. Their divorce is still pending for yrs. she lives in California and my dad lives in Az. The real estate agent sent out a document 3yrs ago for her to sign the papers , that she have nothing to do with the house . The problem, she did not want to sign it . And now my dad wants to try purchasing a home again , is there any way he could buy a home without asking her to sign anything? She don’t like my dad to move on so she’s giving him a hard time.