Whenever you have people working in a foreign country in a way that potentially violates immigration or labor law, it’s safe to assume that there is some coercion going on. Then you throw in the fact that it’s children, and you’re guaranteed that coercion is happening. In my mind, that’s the question. What choice did the kids have? Not much of one.
Bear in mind that the company could have hired locals and it could have hired adults, which would have put it on the right side of the law and would have avoided language issues. But the company did what it did, and what you see in situations like this all around the world is that it’s almost always because they can save money by treating their employees worse, overworking them, underpaying them, ignoring labor law, and knowing that the employees won’t have any recourse when they’re abused.