I think you misread my post. " each of those schools that rejected him" is referring to the group of schools. All the schools that rejected him. Not that all the schools rejected him.
I only skimmed the article (it’s long and I’m not very interested in this) but I didn’t see anywhere that said he was suing Harvard. I found a reference to a lawsuit against Harvard and UNC that someone else made. I did ctrl+f for “sue,” “suing,” and “lawsuit” and didn’t find anything about this guy suing Harvard.