Upcoming appointment and Anexo III LMD

I finally have my appointment in the NYC consulate scheduled for April 2026. I applied under Anexo III. My mother applied via Anexo I and went to her appointment in February 2024. Her application was routed to Buenos Aires because that's where she was born. The Consulate there (likely due to the backup) has not yet issued the Spanish birth certificate. The Anexo III instructions say I need to present a Spanish birth certificate from my mother. What do I do? Nobody picks up the phone or responds to our email inquiries in Buenos Aires. I have a copy of my mom's Anexo I and inscripción de nacimiento stamped by the NYC consulate. Do I show that?