Celebrity seer John Cohan, who wrote about his friendship with Wood in his book Catch a Falling Star, was planning to reveal the truth about what he thinks happened to the actress on the last night of her life in a sequel.
However, he is so upset about the latest round of allegations following the re-opening of his friend's death investigation he is speaking out now.
Cohan claims Wood's former lover, who she called Stinger, had threatened to tell her husband Robert Wagner about their affair - and he was "close by" on the night she died.
When the case was initially closed, it was ruled that Wood accidentally fell overboard from her husband's boat miles out to sea off the coast of California after a boozy night with Wagner and the couple's guest, actor Christopher Walken.
But Cohan tells WENN, "Anyone can clamber onboard a boat and then leave. I believe Stinger came onboard and he confronted Natalie and he is responsible for her death."
The psychic claims Wood had been madly in love with the "blue-eyed, blond-haired" hunk but he turned on her towards the end of a year-long romance and threatened to go public with the affair if Wood didn't pay him a small fortune.
Cohan adds, "Stinger was someone very important to Natalie. Our mutual friend, Roddy McDowell, told me he had died of AIDS many years after she did. That's all I know. I never asked for his identity. I didn't want or need to know. of his death.
"I am coming forward now because I feel I have a mission of love. I'd like to let people know the mindset of my Nat. She was so together in the end, a very bright woman. She did not slip overboard to her death or take her own life even though she wasn't happy with R.J. (Wagner).
"And all this talk about an argument between R.J. and Natalie over a romance with Christopher Walken is nonsense. There's no way they were involved. I stake my reputation on it. Natalie thought of Chris Walken as a buddy, which she firmly told me."
Cohan is convinced he has the story of his friend's death spot on, because he claims Wood has confirmed his theory during visitations from beyond the grave.
He adds, "Natalie's visitations confirmed what Roddy always said to me too - Stinger went both ways in the latter years, women and men.
"I am hoping that this revelation takes the investigation to another point and helps to clear Robert Wagner's name. He was not a saint but he did not kill Natalie, as has been suggested. They're making him into something he's not.
"Someone came onboard the boat in the middle of the night when Christopher Walken and R.J. were out of it. There were no eyewitnesses. So much has been made of an argument earlier in the evening. That had nothing to do with Natalie Wood's death."