I want to know the answer to the following question:
Who placed the chapel's cornerstone?
All the background I'm provided with is that "The Blessed Virgin was proclaimed patroness of the city under the title of Virgen de los desamparados (Virgin of the Forsaken), and Archbishop Pedro de Urbina, on 31 June 1652, laid the cornerstone of the new chapel of this name.". Is that enough to answer the question?
Answer: yes