Well, maybe you can at least confirm you see the same :-)
1. When I open the search widget I see that my second built in drive is excluded from search. Why I don't know, I can delete it but it will come back when I close and open the settings widget. It doesn't tell me where it searches, but that's ok.
2. I check the exclude folders in baloofilerc: cat ~/.config/baloofilerc | grep "folders\[" and this shows me a completely different picture, here the second partition (Win10) of drive 1 is excluded
3. I run baloosearch looking for a file which I know is on the excluded Win10 partition, and guess what it's found?
So to conclude, the settings in the search widget do not match the config file, and the config file is ignored anyway?