TestPartner Microsoft Excel 2013 - Runtime error '48' Error in loading DLL on Excel.Application

We had a QA user who recently had Microsoft 365 pushed to their desktop. This caused our QA user to lose the ability to run our automation, which requires Excel's VBA library. We had it rolled back to Microsoft Office 2013, but the user is still unable to run reports. The error that results is "Runtime error '48': Error in loading DLL", and, when we click debug, the highlighted code is trying to create a new Excel.Application object.

 

The Object Browser indicates that the Excel COM object is coming from the Excel.exe file that was installed as part of Office version 15 (that is, Office 2013). Our team is unsure of how to debug this issue, it could be a registry issue or some corrupted part of the re-install. What debugging steps should we take to address this issue?