Two reports from the John Batchelor Show on CBS Audio Network, Pacific Watch segment with Jeff Bliss, Special Edition:
"Two million migrants --including 200,000 unaccompanied children and 1.1 million single males -- encountered at the border by the end of the year" (Audioboom Podcast)
"Mexican Cartels use China's Tik Tok to recruit US-based human traffickers" (Audioboom Podcast)
Big business, yes? I believe you can get an idea of how big from a May 31, 2019 Forbes report written by Kenneth Rapoza, a Forbes Senior Contributor (emphasis mine):
Central American Migrant Remittances Breaking Records, Beats Foreign Investment
I think the Forbes report could explain the mystery of why the crime cartels are now outfitting 'migrants' with wristbands that contain too much data to simply identify whether the banded 'migrant' has passed through a cartel checkpoint on the way to the U.S. southern border. The governments of the Central American nations, who seem by now to be almost openly in league with the cartels, would need to keep close track of who is entering the USA. They would want an estimate of the remittances they can expect from migrants who get work in USA. If they're doing more than keeping tabs -- using gang members to remind workers with jobs in the U.S. and their families to keep up the remittances, the workers would be in effect slave labor.