SBA lenders make their money by packaging and selling the loans to third party investors. Try to find a non-bank type of lender who may be more aggressive and much more open to coaching your son through the process. In fact, try to find a few of them.
As a borrower from the SBA it is not of your concern where your paper ends up, the SBA insures the paper up to 70%, it's how SBA 7A loans can be had at below prime for borrowers.