If the consumer can’t repay the loan it shouldn’t be made.
1026.43(c) Repayment ability. (1) General requirement. A creditor shall not make a loan that is a covered transaction unless the creditor makes a reasonable and good faith determination at or before consummation that the consumer will have a reasonable ability to repay the loan according to its terms.
If you can’t qualify the loan, I recommend following your adverse action procedures. If they reapply with a co-applicant you may be able to qualify the loan under either ATR or one of the QM rules.