It has been my experience that automating Microsoft apps or any apps that were not built by your team is a challenge. Have you looked into the settings in Tools\...Project Properties\Open Applications\MSAA?
https://support.smartbear.com/testcomplete/docs/reference/test-objects/controls/desktop/msaa/index.html
There are quite a few advanced settings in 'Open Applications' as well as 'Object Mapping' you may find useful. I can't speak to your specific situation but I have used MSAA to expose controls buried in Microsoft tree objects that were otherwise not accessible (or just flakey in automation).
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Good luck!