Billionaire hedge fund manager Ken Griffin, who took his investment firm and largesse to Miami two years ago, is once again making a name for himself in Chicago philanthropic circles. Griffin Catalyst, a civic engagement initiative he launched last year, announced a $10 million donation Wednesday to Northwestern Medicine to fund advanced research and treatment into esophageal diseases. The Citadel founder’s largest gift to a Chicago organization since he left for the Sunshine State in 2022 will also rename the acclaimed Northwestern Medicine program as the Kenneth C.