It's not clear when Carol first met Castaneda, but on October 3, 1972, as Kathleen Adair Pohlman, she filed paperwork for a change of name to Elizabeth Austin. All of the woman close to Castaneda had their names legally changed at least once. According to lecture notes recorded in April 1995 she purportedly first encountered Don Juan in Mexico City sometime in either late 1966 or 1967 at age 19. This account differs from that given in Castaneda's book The Eagle's Gift. In 1973 Carol supposedly left either with or shortly after Don Juan (the events vary according to which book one reads, The Eagle's Gift, or The Art of Dreaming).

Richard Jennings, who was invited to attend Castaneda's private Sunday sessions and was deeply involved in the group from 1995 through 1998, believes that Castaneda's group of close associates during the late 1970s and early 1980s likely numbered less than two dozen. A reportedly pivotal event at the time was the defection of Carol Tiggs. Shortly after joining the group she tried to break away. She attended California Acupuncture College, married a fellow student and lived in Pacific Palisades.

Carol was reunited with Castaneda most likely in the fall of 1985 at a lecture at a Phoenix Bookstore in Santa Monica. On April 5, 1988, as Elizabeth Austin Carol, Carol again filed for a change of name, this time changing it to Muni Alexander. The name change was effective May 20, 1988. In 1993 Castaneda's The Art of Dreaming was published by HarperCollins. The Nagual woman figured prominently in this work. She reportedly rescues Castaneda from the "foggy, yellowish world" where he had supposedly gone to rescue the Blue Scout (said to be Patricia Partin.) On September 29, 1993 Carlos "Aranha" married "Carol Muni Tiggs Alexander" in Las Vegas. The marriage license lists this as Carol's first marriage, her date of birth as November 24, 1957 in Arizona, and her parents as John Michael Alexander and Carol Tiggs of Arizona. Just two days before Carlos Castaneda had married Florinda Donner in Las Vegas.

On April 27, 1998 Carlos Castaneda's death certificate was signed. It reported that his death occurred at 3 AM on that date. The death was kept secret until June 19, 1998 when the Los Angeles Times' obituary reporting Castaneda's death appeared on page 1. The following day an obituary in the New York Times reported that Castaneda's adopted son, C. J. Castaneda, was responsible for making the death public. On August 2, 1998 Carol spoke at the Ontario Intensive Workshop, Ontario Convention Center, Exhibit Hall A. Carol has not been seen in public since.