The sudan slave redemption program

The African nation of Sudan is one of the poorest countries in the world. The average income per person there is about $500 per year. The practice of human slavery is very much alive in Sudan. In particular, members of the Baggara tribe raid territories occupied by members of the Dinka tribe. The Baggara capture Dinkas and then sell those captives into slavery. The average price of a human slave in Sudan is about $15 (that’s the equivalent of more than a week’s wages for the average Sudanese worker). Slaves are branded with the names of their owners and put to work as cooks, house cleaners, field laborers, and in other jobs.
An international humanitarian organization is trying to free these slaves. In a process called “slave redemption,” the organization buys slaves from their owners, at a price generally of about $50, although sometimes as much as $100. The organization then sets those former slaves free. The organization says it has purchased the freedom of about 3000 slaves in the past 15 years.
Did this slave redemption program accomplish its goal of freeing people from slavery?