Even if you went back and redid the HUD (which is all you could do because the GFE cannot be changed), you required this fee as part of the loan which puts it in the 10% tolerance so most likely, you'd end up paying 90% of the fee anyway.
If I were the borrower...well, suffice it to say, I wouldn't be paying to fix your mistake.
This is an error that needs noting and training to guard against it happening again.