I don't know if you will call it stunt casting or star casting, but I saw former Charlie's Angels star Cheryl Ladd in "Annie Get Your Gun" 20 years ago this coming January. I believe she took the role for two months, so maybe it was 'stunt casting'. Whatever it was - she was incredible. She had the audience in the palm of her hand, She could sing, she could dance, she could act - she wasn't Cheryl Ladd, she was Annie Oakley!
I've often wondered why she had never done a Broadway musical before (or since!), and how they ever thought of her in the first place to fill in the role for that short time frame.
Too bad they didn't think of her for 'Hello Dolly' to replace Bernadette Peters (or Bette Midler).