Name it Booker T Washington (Redskins) and call it a day.
Washington State did something similar. They renamed King County (originally named for a short-lived Vice President who served 6 weeks in 1853) so that it is now named for Martin Luther King, Jr.
The Jefferson Memorial would be easier to fix. Just rename it the Sally Hemings Memorial. Instead of removing Jefferson's statue, add one of Sally (but it would have to be 60% the size of Jefferson's statue because of the "three fifths" clause).