Maybe these kids were distinctly troublesome all their lives. Maybe parents did all they could, enlisting psychiatrists, psychologists, teachers, family, counselors. Maybe family and neighbors knew these girls grew up before their time, and although they were still teen aged children, were as functional as adults, but did not comport themselves honorably. It is true that we don’t know where the parents were. Drug addicted, or alcoholics, or simply not interested, or maybe they were excellent parents, overwhelmed with so many difficulties too hard to explain. It is possible the professionals did all they know what they could do. Is it not possible these girls wanted, perhaps insisted on freedom out from under their parents’ protective wings. Also, i have difficulty in thinking of this as true slavery, which was often a lifetime of brutal slavery, with many dying from extreme servitude, and with force being used against them ALL their lives.
Sure, all that is possible. Whether it is probable, or whether, in fact, the possibilities you pose comprise the majority reasons “why” human trafficking exists, is to be determined. Even if the reason possibilities that you raised were true in the majority of cases, it does not excuse or “normalize” human trafficking, in any way.