Bangladesh, May 4 -- In the hushed hills of Boqueron, a small region in the Dominican Republic, Kenia Castillo recalls the last moments with her son, Rafelín Martínez Castillo, before he embarked on a journey that would end in tragedy. Rafelín, a skilled craftsman, left behind his woodworking tools to pursue the promise of a better life in the United States. Little did he know that his quest would lead him into the heart of a deadly human trafficking network spanning across Mexico.

The story of Rafelín Martínez Castillo is just one among thousands of migrants who have fallen victim to the perilous journey through Mexico. Like many others, he entrusted his fate to smugglers who promised safe passage across borders...