Zeiders claimed she instructed two men to attack Denham in her defence but denied her own participation in the assault.
She also said a man she had never seen before emerged from the bushes, kicked Denham in the head, and started going through his pockets.
Zeiders claims she watched the ambulance arrive, at which point the man walked away and refused medical treatment.
Denham's family say Zeiders' allegations are absurd and that he would not be interested in masturbating on her lawn because he was gay.
"He never would have attacked anyone," the victim's sister Maureen Tourigian told the Tampa Bay Times. "Anyone who knows know him know that, and that he never would expose himself to a woman. He wasn't interested."
A witness reportedly told cops he saw Zeiders and her pals beating and kicking Denham, and that he heard the word "pedophile" used during the attack.
Dan Kane, Denham's life-long partner, believes the trio beat his companion to death after attempting to rob him and discovering he only had a few dollars in his pocket.
Kane rubbished the masturbation story, saying it would have been completely out of character for Denham, especially considering his sexual orientation.