Afaik they need their workers because their managers and engineers can't get the jobs done with indigenous workers.

Algeria did IIRC begin to push for indigenous workers because of unemployment/underemployment and so on, though.

The Chinese managers might want to cling to indigenous workers that are productive and kind of recommend them to some form of Chinese-host state trade agency,for later employment.
This could create a sub-set of China-loyal indigenous worker (familie)s.