In the case of rubber the big companies do provide better jobs for the families they employ than anything else, ensure the family gets modern medical care (as opposed to "witch doctor" care anyone not working for them gets), and the children do go to school and so have the ability to get a better job latter. The companies looks the other way in harvest season then families are taking their kids with them to work, so long as the kids are in school. Child labor for sure, but you can honestly argue that the children are better off despite that.

You can decide if you accept that as better or not, but it is a reasonable argument that child labor isn't always the worst possible.

Sadly I don't think in the case of cobalt the above applies.