I was born and live in Monterrey, México. This is an interesting story, but I have contacted the city chronicler and some other sources of historical info about Monterrey, both people and books. I have contacted Israel Cavazos (city chronicler), Catholic Father Aureliano Tapia Méndez (another researcher of city history), Armando Fuentes-Aguirre best known as "Catón" in México, Fernando Alanís, and several history researchers at the local University of Nuevo León, and nobody had any info or clue or idea that there was a robbery in the Old Monterrey. You may wonder Why did I make such a big research, and the answer is because Brian McDonald, a treasure hunter from ClearWater, Florida, exposed in this forum the historical robbery of Monterrey (city banks and cathedral) that, according to him, happened in 1881. The suppossed gang of bandits included both mexican and american bandits. Mexican bandits had a leader called José Estrada. On the other hand, american gang included: Zwig Hunt, "Curly" Bill Broucious and others.
If you want more info or help, please let me know, my name is Ricardo Acosta my e-mail address is:
ricardoacosta@hotmail.com