ebb tide - For what its worth, there is no Bishop Pedro Mercado listed on the Church Hierarchy website.
http://www.catholic-hierarchy.org/bishop/llm2.html
I don’t understand your comment, what is the significance of his non-inclusion in this list?
I was just pointing out that no bishop has yet been identified as issuing the declaration of “excommunication”.
Based on the following link (from 2013) the list of the members of the Episcopal Conference of Colombia includes Pedro Mercado Cepeda. Interestingly enough, he is listed as a priest, not a bishop.
https://www.wola.org/files/130419_cec_eng.pdf