Although I do not know your specific scenario, you can launch excel reports from a CAB application. I will share the steps it took me to do it which you might find useful:
Create a new SCSF solution using the Guidance Package.
Create a new Excel Workbook project in the solution.
Add the Module and ModuleController classes to the Excel Workbook project (you can copy this from any other module generated with the recipe).
Add an entry in the profile catalog to load the module .
Having performed the previous steps you will have a VSTO project, loaded as one of the modules of your application.
Please let me know if this helps.