A university doesn't have a "main" dean. Colleges do. At a university, each college (e.g. Arts & Sciences, Engineering, Education, Home Economics -- now called something politically correct, but there's always a surviving college that used to be called that) has a main dean.
At a small liberal arts college there's a main dean who is the chief academic officer, analogous to a provost at a university.
I'm guessing this one wasn't actually in charge of a college, but bore some awful title like Dean of Diversity and Inclusion, or Associate Dean of the College of Arts and Sciences for Diversity.