Todd Peterson in The Negro Leagues Were Major Leagues lists the game as June 9, 1996, but news articles confirm it as June 8th game.
Mariners at Brewers - July 31, 1996
Royals at Tigers - August 24, 1996
Todd Peterson lists a game between Monarchs and Stars being played on this date. Henderson does not have a jersey for this game. I'd be surprised if the Royals didn't do a Negro League Tribute game this year.