So, since your original post you stated you just found about this. Does that mean he lied on his employment application? How would your company like it if he was asked and lied in response? Do you even ask that as part of the hiring process?

Now as far as the original concern, have him answer the question and if he is denied the visa, so be it. Send someone in his place.

People say that China has no way of knowing his background, but I would be do sure of that with all the hacking issues we read about in the news.