1. We don't know if these workers (or other workers) are pursuing this in court. Legal and illegal pursuit are not mutually exclusive, at all.
2. If the factory owner is not paying wages because they are already bankrupt, there is nothing that the legal system could reasonably do about that.
3. The workers would not have recourse to claim funds from Apple: I'm not aware that they would even in any country with a "good" legal system.
It strikes me as a long stretch to reach "bad/corrupt legal system" as a conclusion.