You are factually wrong.
'Global slavery index' is not a credible source, even according to Wikipedia.
I'm sorry I spent 2 minutes of my life looking it up - I should've known better.
This conversation is over. I can't trust you to not throw random crap a google search produces that supports your fantasy that I then have to spend brain cells to debunk.
Then pick a different one. Which measure did you use to come to your conclusion?
I suspect you didn't use one at all, because I am not aware of any measure of "slavery" that correlates positively with any measure of investment activity.
Labor practices and protections are much better in countries with high economic investment.