"They are afraid of staying in Greece" due to possible capture by Turkish state agents, law professor Nikos Alivizatos, a member of the defense team, said at a press conference on Wednesday.
He further said that the eight officers will seek to stay in another EU country or elsewhere, if granted access and travel documents.
Greece's Supreme Court blocked the extradition of all the eight men in January 2017, arguing that they were unlikely to face a fair trial in Turkey.
Two of the eight men have been granted asylum, but the Greek government contested the ruling, and the country's top administrative court is to decide on the case soon.
The refusal of other EU countries such as Germany and the Netherlands to extradite Turkish diplomats and officers also caused problems in their ties with Ankara, Vassilis Papadopoulos, legal coordinator of the Greek council for refugees, said.
Turkey accuses the eight men of involvement in efforts to overthrow the government. The officers denied the accusation.
More than 250 people were killed in the process of the coup on July 15, 2016. Ankara swiftly blamed rogue elements in the army, saying they were operating as part of a larger network run by Fethullah Gulen, a US-based cleric, Presstv Reported.
Thousands of military and police officers have been jailed or dismissed from their jobs over an alleged role in the coup. The eight who fled to Greece have repeatedly claimed that they feared for their lives back home.
Turkey and Greece have a history of strained relations, especially with regards to territorial disputes and the situation in the technically-split Cyprus. Turkey has warned that it would cancel agreements with Greece on the repatriation of refugees if the renegade soldiers are not sent back.
A further complication arose in March, when Turkish troops arrested two Greek soldiers for illegally crossing the border into Turkey and allegedly entering a prohibited Turkish military zone.
They have been detained for the past two months. Turkish President Recep Tayyip Erdogan last month proposed soldier swap, which was flatly rejected by his Greek opposite number Prokopis Pavlopoulos.