Not only does he not apologize, he states that Limbaugh flatly denies the quote, then goes on to say, [paraphrase]”nevertheless, there are many other quotes by him that members of the African-American community find offensive”. So, he actually pours fuel on the fire by dredging up other so-called “quotes” that have not attribution at all.
Ah, the old “fake but accurate” defense.
Unfortunately there are some in the African-American community who spend the better part of each day being offended. It’s the politics of social grievance, and there are other groups that practice it.