The Crown Office and Procurator Fiscal Service has confirmed it has received a report from the Scottish Fire and Rescue Service concerning the outbreak of the fire which devastated the luxury hotel in 2017.
Partners Simon Midgley, 38, and Richard Dyson, 32, from London, died in the blaze on the banks of Loch Lomond near Balloch, West Dunbartonshire on the morning of December 18, 2017.
Last month it was revealed the repairs to the five-star hotel will cost £23 million.
Assistant chief officer Ross Haggart, director of prevention and protection at the Scottish Fire and Rescue Service, described the investigation as 'extremely complex.' He said: "The SFRS investigations into the circumstances surrounding the incident at Cameron House on December 18, 2017 have been extremely complex.
"We have now finalised and submitted our reports on the incident to the Crown Office and Procurator Fiscal Service's Health and Safety Investigation Unit for their further consideration."
Once all final reports have been submitted the Crown will determine the cause of death and decide whether or not there should be prosecution proceedings or a Fatal Accident Inquiry.
The Crown has also received a death report from Police Scotland, but is still awaiting a prosecution report from the police.
A Crown Office spokesman said: "The Crown is committed to ensuring that the facts and circumstances surrounding the deaths of Simon Midgley and Richard Dyson are thoroughly investigated by the relevant agencies, fully considered by COPFS and, in due course, aired in an appropriate legal forum.
"The nearest relatives will continue to be kept updated in relation to any significant developments."