The last exam that I was involved in, where HMDA was reviewed, the examiners double checked our income calculation in the file and matched the number up to what we reported. Is this still happening in exams?

The department that is double checking HMDA in my organization is not double checking the income calculations or how DTI was calculated. Should someone be doing this? They are just checking to make sure the income/DTI on the underwriting worksheet matches what is on the HMDA worksheet.

As long as the worksheet reflects the income and DTI that was used to actually make the loan decision, that would be your concern. Otherwise the worksheet is useless.