Yeah, he would defend right winger or bigot. He would attack anyone not right wing. The rights of people who were not white conservatives did not concerned kirk. He was literally against civil rights, openly. Blacks are all stupid and trans are all groomers. They all should be fired.
I have no idea about what happened between that "left leaning professor" and student. But there is about zero reason to believe what right wing activist like Kirk says about the issue. As far as he was concerned, left need not exist and need to be punished for existing.