Had the premise of the movie been different, it may have been plausible, but as a well known regular run of the mill debt relief program that everyone knows about.... not so much.
In the world within the movie, it's clear that people can go missing enmasse, and no one ever goes looking for them or raisinging awareness of it.
Keeping in mind that the people the program is taking or enslaving, are people who are deep in debt. Not exactly the most able bodied people. They then proceed to enslave them to doing the most meaningless of all labors, clear cutting some forest jungle land for a pipeline.
Why not just spend the money and get the job done properly with proper crews and equipment.
Yes your free labor force will eventually get the job done, but practically it would take them 20 X as long as a real crew, thus delaying the contracting companies progress.
