The formal identification of Mr Didier, an NHS worker with family links to Arkansas in the US, has been complicated by the fact that he is not a UK national.
It is thought it may take at least another day to obtain dental and other records from his home country to aid identification.
Mr Didier died primarily as a result of drowning.
It is thought he committed suicide and might have also used another method, such as an overdose.
The couple, both from Surrey, had been holidaying on the Norfolk Broads with the woman's 13-year-old daughter for about a week and are said to have enjoyed meals at local pubs.
Detectives are working to establish how long the girl was alone on a boat before she was found and the bodies recovered.