NYS Step-Parent adoption, absent mother

Hoping there is some bits of wisdom out there for us... here's the story. My fiance has had custody of his daughter (now 15) since she was 18 months old. My SD has asked me to adopt her, and I of course am very willing to do so. The bio mother has never paid child support and has never exercised her right to visitation. The biological mother lives in Arizona (we are in NY), we know she remarried and had additional children, but we do not have an address for her. My fiance attempted to contact her at her last known email address and we did not receive a response. He contacted the biological mother's mother who told my fiance that she was not comfortable giving out her daughter's contact information without her permission (by the way, never once asked about her granddaughter). We are getting married in October, the 3 of us (finance, SD and myself) are walking down the aisle together as a family, and would like to include her adoption as part of the ceremony in some form or fashion. Here are my questions: 1. Has anyone had any luck starting the adoption process before actually getting married? 2. If bio mother refuses to consent, can we use the fact that she hasn't paid support or had contact in 13 years to show clear abandonment? 3. If bio mother does rear her head at this point, can she force my SD to see her? She's a total stranger! and the most important question, how do I protect our girl from getting hurt by the bio family? I almost feel like we're asking for trouble by starting this process.