Local guide Henri Haiti took Ramin on a goat hunting trip in the mountains of Nuku Hiva and is believed to be the last person to see him alive.
Charred bones, teeth and melted fillings were found in the ashes of a camp fire in a remote valley on the island of Nuku Hiva in the Pacific Ocean, a week after he went missing.
Testing in Paris will conclude whether the ashes belong to Mr Ramin, but is expected to take several weeks.
A team of 22 police officers and the army are conducting the search.
Mr Haiti returned to Ramin's girlfriend, Heike Dorsch, saying that her boyfriend had had an accident and been injured. When she went to look for him and tried to call for help, she was allegedly chained to a tree and sexually assaulted.
Hours later, she managed to escape and called the authorities.
The couple were on a worldwide sailing tour when they stopped off at the island in French Polynesia.
Reports in Germany said they moored their catamaran on September 16 while on a trip of a lifetime.
According to the Mirror, Moby Dick author Herman Melville claimed he was once captured by a tribe of cannibals on Nuku Hiva but escaped.