John Miner was an attorney who investigated Marilyn's death. He claims Ralph Greenson played him his and Marilyn's private tapes. Decades later, he wrote a transcript from memory. The transcript doesn't fit with how Marilyn spoke, at all. This has been discredited as nonsense by Marilyn researchers.
He believes Marilyn died from suppository/enema due to the discolouration of her colon. It has also been reported that he believed it was an injection. However, the discolourisation occurs in death anyway so doesn't prove this as the cause. He was not a medical examiner. Many ME's do not believe in the enema or suppository theory.
He claims he was present at the autopsy, however, the coroner Dr Thomas Noguchi does not recall John Miner being present at the autopsy.
Again, he is not deemed a reliable source.