The mortgage sector is one of the more complex industries to work in, especially in a call center. There is a lot of information that you need to gather to understand the calls to their full extent. That often results in confusion and misinformation with outdated QA.
The fact is that spreadsheets and unmanaged QA systems are not up to the job in the mortgage sector. You need a system as capable as you need, handling vast amounts of data and calls.