I agree with my colleagues. The key will be to show his ties to Pakistan so that the US government is satisfied that he does intend to return home after his brief visit to the US. Bank accounts, employment verification letters, property titles and evidence of other family members staying in Pakistan that rely on him for support, such as a wife and children if any, would all be helpful.
This information is provided as a courtesy based upon the limited information provided in your post and does not constitute an attorney-client relationship.
It is difficult to obtain a visitor's visa with these limited facts. The most important thing is to provide documentation showing his ties to Pakistan. He needs to have a stable job, that he will be returning to and other documents such as a lease showing his ties to Pakistan. As always it is best to consult an immigration attorney.
Alexus P. Sham email@example.com (917) 498-9009. The above information is only general in nature and does not constitute legal advice. It does not create an attorney-client relationship.
Visitor visas are tough to get especially with all of your family members being present in the U.S. With all of them here, DOS may believe that he has the intent to remain here. His bank account is but one factor that DOS will review. There are many other avenues to prove he has the intent to return home. Please retain counsel to assist.