Under what condition does Cynthia Knox agree to assist Spenser in the novel, The Widening Gyre?

Cynthia Knox is one of the older women who participates in Broz's orgies. She is beautiful and classy, and feels both sated and stained by her experiences with Broz. She knows that she is unhappy and dissatisfied with her life, and her solution is to punish herself with drugs and casual, demeaning sex. Spenser urges her to find another solution, and she agrees to help him with his investigation in any way she can, so long as her reputation remains intact.