If Foxconn workers had either average or worse-than-average mental health (in their country), this outcome appears to be positively impacted by their employer.

If Foxconn workers had either average or worse-than-average mental health (in their country), this outcome appears to be positively impacted by their employer. This seems like a reasonable assumption, unless you have some countervailing information. Calling out unspoken assumptions can be useful, but it's not a refutation unless the assumptions are unreasonable or demonstrably wrong.