"We can only tick the right boxes and answer what is required for the [New Zealand] immigration department.
"But we are keeping our fingers crossed and hopefully things will pan out for the better."
A spokesman for New Zealand Foreign Minister Murray McCully said Nakarawa's case was under review but further details were unavailable at this stage.
The 117kg lock is the only Fiji player affected by the ban, although many top officials of the Fiji Rugby Union will not be allowed to attend the World Cup because of their military ties.
Fiji avoided a confrontation with New Zealand authorities last month by omitting the 23-year-old from the team that travelled to Dunedin for a test against the All Blacks.
Wellington has repeatedly said the ban will remain until there is evidence of substantial progress towards the return of democracy in Fiji.
International Rugby Board chief executive Mike Miller said in June that he hoped New Zealand would change its stance and allow Fiji to field its best team.
- NZPA