The publicity-shy 26-year-old was told she would have to take her singlet off at the official weigh-in - a top bearing the words "Connor Morris RIP" - to make the target weight.
She said she was mortified at the prospect of removing the shirt dedicated to the memory of Mr Morris, a patched Head Hunters gang member, and at having to strip down to her underwear in front of a "media circus".
But at the weigh-in, despite not removing clothing the extra weight inexplicably disappeared.
"Obviously I'm not comfortable with standing there with just a bra on and there would have been a media circus. But I jumped on the scales and I was exactly 68, so I feel like that was Connor, [saying] 'leave your shirt on'."
Ms Elder-Holmes proved a knockout in her boxing debut, where she and Adams were part of the undercard for the Joseph Parker v Irineu Beato Costa jnr main event.
And though she says Adams was a tough opponent, Ms Elder-Holmes said much of her sparring with her trainer - amateur boxing champion Hurricane Doyle - had been harder.
The fight lasted three rounds and at the end Ms Elder-Holmes was unanimously judged the winner.
The daughter of the late Sir Paul Holmes paid tribute to Morris after the win, pointing to his name on her singlet and later on social media.
"Thank you Connor Morris for everything you taught me and your amazing Morris family. I wouldn't be who I am without you and I know your [sic] always with me. #onelove."
Her motivation for being in the ring was that $100,000 would be donated to Hospice Waikato.
Asked if she planned to continue boxing, she said: "I don't really look too far in the future. I'm just happy that it's over."
Adams said her training meant "it was nothing out of the ordinary getting hit in the face" but the first thing she did after the bout was try to get her breath back.
"Millie was a really good opponent. But I'm really proud of myself and extremely glad that I did it."
In other bouts at the packed-out Fight for Life, former All Black first five Carlos Spencer succumbed to the flurry of punches unleashed by former professional boxer and Warriors standout Monty Betham.
In the main event, Parker landed a devastating knockout blow on Costa jnr in the fourth round, making the year his most successful as a professional boxer.
