Lili Bernard has accused Cosby of drugging and raping her in Atlantic City in 1990.
She had "Women's Lives Matter" painted on her body.
The actress, who played his TV daughter, "always" saw darkness in Cosby.
Andrea Constand, who was expected to go away and keep quiet, wound up testifying against Cosby in a criminal trial last June that ended in a mistrial.
Bill Cosby grants a rare interview, but will not testify at his criminal trial.