Yes. Ian Wallis, back when GSN was first established, got a message from David Schwartz, stating that celebrities, who were on game shows after 1973, must have their appearances cleared in order for them to air on that channel. Here's a list of all the stars who have said no to reruns on GSN:
Adam Arkin (Match Game '77, Match Game PM)
Anitra Ford (Match Game '76)
Betty Thomas (Password Plus, Body Language)
Fern Fitzgerald (Body Language)
James B. Sikking (Password)
Jay Leno (Tattletales)
Steve Kanaly (Match Game syndie -- though his two PM episodes did air at least once apiece on GSN, as did his week of All-Star Beat The Clock)
Valerie Bertinelli (Match Game '78, Match Game PM -- though three of her $20,000 Pyramid episodes did air on GSN)
David Leisure (Super Password)