A former fashion executive and his gardener admitted having a "violent struggle" with a man they believed to be an intruder who later died.
Ricci Gallagher was found injured at a house owned by Richard Glanville in Little Burstead, Essex, in July 2015.
An inquest heard Mr Glanville told police he feared for his life after Mr Gallagher had smashed his way into the house with a baseball bat.
The coroner recorded an open verdict into Mr Gallagher's death.
Last year, prosecutors said they would be taking no further action against Mr Glanville and gardener Paul Pumfrett - who had both previously been arrested as part of a murder investigation - due to insufficient evidence.
Mr Glanville worked for Aurora Fashions, owner of high street brands Oasis, Coast, Warehouse and Karen Millen until 2013.
During the hearing at Chelmsford Coroner's Court, former Essex Police detective Marina Erikson said there was "uncertainty" over the reasons behind the events.
On 30 July 2015, Mr Gallagher, 46, called 999 to report a fire at his wooden house in Viva Place, Blind Lane, claiming someone had poured petrol on his roof.
Several phone calls followed, the detective said, before a final call was made in which Mr Gallagher asked for an ambulance.
Two other voices were heard in the background, one of which said: "You're going to need more than that, mate."
Paramedics found him bleeding on the patio outside Mr Glanville's farmhouse in nearby Sudburys Farm Road.
Mr Glanville and Mr Pumfrett said Mr Gallagher had run towards the house, claiming he was being followed, carrying a baseball bat before breaking a patio window and going inside.
They admitted having a "tussle" with Mr Gallagher while they tried to disarm him as they "feared for their own lives" and wanted to protect the property.
Former Det Ch Insp Erikson said questions remained over the level of force used and whether Mr Gallagher had fallen down the solid oak stairs.
He died in hospital from head injuries a week later. Experts were unable to say exactly how the injury had occurred.
Toxicology tests suggested he had used cocaine in the hours before his death.
Coroner Caroline Beasley-Murray described the police investigation as "very challenging".
She expressed her sympathies to Mr Gallagher's widow, Linda, and said he was "clearly much loved".