DIANA Quer's post-mortem has shown the sixth-former and model from Pozuelo de Alarcón was strangled to death and that her self-confessed killer's claims he ran her over by accident are false.
As yet, it is not known whether Diana, 18, was sexually assaulted, and further tests are required, but initial reports hinted this may be the case.
José Enrique Abuín Gey, 41, known as 'El Chicle' ('Chewing-Gum') because of a speech impediment when he was at school, had insisted he knocked Diana over whilst reversing in the dark and then panicked, throwing her body down a well inside an industrial estate in Rianxo (A Coruña province), about 20 kilometres from her family's holiday home in A Pobra do Caramiñal.
He even called for forensics to examine the back of his car again.
But the autopsy showed no signs of external injury, not even compatible with a minor blow from a rear-view mirror.
Abuín Gey, in another version, said he dragged Diana into his car when he saw her walking back from the fiestas in A Pobra at around 02.20 on August 22, 2016, bound her hands and tied her by the neck to the passenger seat headrest with reins from a bridle.
He said she 'kept kicking and struggling' and that although he tried to rape her, he was unable to do so.
It is not known whether he strangled Diana by hand or with the reins, but the forensic report confirms she was killed inside the warehouse and that she was already dead before she was thrown down the well.
She was naked and tied to two concrete blocks to prevent her body floating to the surface.
Police divers, who said they were very distressed at finding Diana's body, dredged the well and found her jacket, handbag and remains of the reins.
Despite being submerged for 16 months, the body was well-preserved as Diana was lying in stagnant fresh water with no flora or fauna, meaning crucial evidence was able to be taken during the post-mortem.
DNA testing showed that only one person had been involved in her murder.
Although Abuín Gey's wife, Rosario Rodríguez, 29, has been released without charge despite initially lying about her husband's whereabouts to protect him, family and friends say she continues to support him unconditionally and telephones him every day in prison.
Diana's funeral is due to be held today (Thursday) near her home in the Greater Madrid region, with only closest family members and friends attending.
Her father, property tycoon Juan Carlos Quer, asked reporters to respect their privacy at the funeral, but thanked them for their sensitivity and ongoing coverage of his daughter's disappearance and death.
He and the young woman's mother, Diana Cristina López-Pinel, from whom he is divorced, are bringing a private prosecution against Abuín Gey using the same lawyer.
Diana: Demon-free and looking forward to the future, says La Voz de Galicia
Diana, whose body was found on New Year's Eve, had been on her summer holidays in A Pobra with her sister Valeria, then 16, and her mother at the house in the beach town the family had owned for 15 years.
The young woman had decided to stay on longer than usual in A Pobra as she was training for her driving test, having signed up at a local driving school where she was taking theory and practical classes.
She is said to have made a number of friends at the academy and had joined them for the disco at the local fiestas on her last night alive.
Tributes to her in regional newspaper La Voz de Galicia described her as mature, grounded and intelligent, and an emotional rock for her younger sister during her parents' divorce when the girls were aged 14 and 12.
Diana was described as the 'mediator' between their parents and Valeria's main support.
After a three-year battle with anorexia, La Voz de Galicia says, Diana had signed up with a modelling agency and was keen to get her own flat, having successfully fought back from her ordeal.
She was said to be happy and relaxed by the time of her death, looking forward to the future and with a strong social network, as evidenced by the WhatsApp messages the police analysed when searching for her.