Simon Midgley, 32, and Richard Dyson, 38, lived together in north London but grew up in Pudsey and Wetherby respectively, died in the blaze at the five-star Cameron House Hotel on the banks of Loch Lomond on December 18, 2017.
Hotel operator Cameron House Resort (Loch Lomond) Ltd was fined £500,000 and a night porter was given a community payback order over the fire at a hearing at Dumbarton Sheriff Court in January this year.
The Crown Office previously decided the circumstances of the deaths had been established and that public interest would not be further served by a fatal accident inquiry (FAI).
However after Mr Midgley’s family, who still live in Yorkshire, asked for a re-evaluation of that decision, an independent Crown Office review concluded an FAI should be held.
A Crown Office and Procurator Fiscal Service spokesman said: “This was a devastating fire which caused two deaths and put the lives of many others at risk.
“During two prosecutions, information on the causes and circumstances of the deaths of Mr Midgley and Mr Dyson were presented in court. Meaningful changes have been made and lessons have been learned from the events.
“Nonetheless, a review by independent Crown counsel with no previous involvement in this case has concluded that there are wider public interest issues around the safety of guests and building fire safety which ought to feature in a fatal accident inquiry.
“The procurator fiscal has now started work to initiate this inquiry and there are a number of legal steps which must be taken before it can commence. The detailed work carried out in the preparation of the prosecutions will be invaluable in this process.
“The families will be kept informed of what will happen next.”
More than 200 guests were evacuated from the building during the fire, including a family of two adults and a child who were rescued by ladder and taken to hospital. They were later discharged.
Dumbarton Sheriff Court heard in January that the fire started after night porter Christopher O’Malley emptied ash and embers from a fuel fire into a polythene bag and placed it in a cupboard which contained combustibles including kindling and newspapers.
Cameron House Resort (Loch Lomond) Ltd, owner and operator of the hotel, admitted failing to take the fire safety measures necessary to ensure the safety of employees and guests between January 14 2016 and December 18 2017.
The company admitted two charges of breaching the Fire (Scotland) Act 2005.
O’Malley, 35, admitted breaching sections of health and safety laws which relate to the obligation on an employee to take reasonable care for the health and safety of people affected by their acts or omissions at work.
He was sentenced to a community payback order, supervised for 18 months, with 300 hours of unpaid work.