Just off the top of my head here, but I believe you may discuss any of the info in a consumer's credit report with the applicant if you need more info. The key is to be consistent and refrain from asking questions that cross the line into prohibited bases under Reg B and FACTA/FCRA. For example, if an applicant has a delinquent payment to a hospital, you cannot treat that debt differently than non-medical related debt or solicit medical info (why was the applciant in the hospital) under FACTA/FCRA. If you keep the questions focused on the circumstances surrounding the debt itself and delinquency, you should be OK.
I've just writed a wrong.