the story goes that Cindy met with D, M, Berry and a couple others to audition and talk. She sang You Keep Me Hangin' On.

I think between all of this and her years of singing with the Bluebelles [[a group they had performed with and watched) was sufficient. This was all happening at a breakneck pace

the infamous New Orleans duet performance was on April 23, 1967. the hollywood bowl show was April 29. I don't know how much of the search occurred earlier. Surely they had initially met with Cindy prior. But the meeting at Berry's house and decision to use Cindy at Hollywood Bowl happened swiftly after NOLA. I don't know of any performance dates in between NOLA and Hollywood.