I thought I may have been on to something...Then again, most likely not...
In June of '73, an 11 year-old girl and her 9 year-old brother were offered $2 each to help a man post handbills on cars in parking lots near Mission Hills. The man, described as being in his 40s-50s with graying hair, dropped off the boy in a parking lot and took off with the girl. She was found a day or two later, drugged, beaten and raped. She survived the attack. The rapist was identified as Robert Lee Ray, who also had a long list of aliases. He was arraigned in October, with a court date of November 13th---right before Karen H was kidnapped.
Ray had a criminal history going back to 1940, including arrests for auto theft and indecent exposure. He also had a lengthy record of sex offenses.
He had married a woman with six kids shortly before kidnapping the Mission Hills girl, and was facing charges for attempted rape of his four teenage step-daughters.
There's nothing else after the October article, just like there's nothing on Sharp/Knapp before the Michelle H kidnapping.