We pull an Equifax Mortgage Solutions credit report for our mortgage applications. It is a tri merge report and we get the scores (EQ, EX, TU) and use the mid score for qualification purposes. Assume that TU has the middle score for a single applicant. On our denial should we list TU as the bureau and the accompanying TU score and key factors or should it list the Equifax Mortgage Solutions as the bureau and the TU score and key factors?

If Equifax Mortgage Solutions is providing you the scores to all three agencies, then they are the consumer reporting agency (CRA) you are getting the score from as they are a CRA themselves.

From the Fair Credit Reporting Act:

"(f) The term “consumer reporting agency” means any person which, for monetary fees, dues, or on a cooperative nonprofit basis, regularly engages in whole or in part in the practice of assembling or evaluating consumer credit information or other information on consumers for the purpose of furnishing consumer reports to third parties, and which uses any means or facility of interstate commerce for the purpose of preparing or furnishing consumer reports."

I agree. Always point them to the source that you received info from.