>There were other considerations like the fact we were actually buying it from large reputable company and what happened was that some employees were doing it with no involvement of the company.

It's their responsibility to police for that. From the perspective of their business arrangement with you, it doesn't matter whether their left hand or right hand is evil; it's not your problem either way.

Is it really hard to find alternatives? Are they really cheaper than non-Chinese sources when you account for these inspection costs?