Fiji Worst Backpacker

My girlfriend and I stayed at the Mana Lagoon Backpackers for a few days around the end of February 2013.
That was the WORST experience of my 4 travels to Fiji in more than 10 different resorts between Mamanucas, Yasawas and Coral Coast.
The Mana Lagoon Backpackers is completely disorganized, rooms are very dirty, roofs are broken with big holes so every time it rains you get wet while you are in bed !!
There's only ONE shower and TWO toilets for the whole resort and both are incredibly DIRTY !! I should have taken pictures of them cause I swear they look like coming out of the Trainspotting movie.
At the time we were there half of the guests were suffering from food poison and the staff didn't care at all. After two days, I started to be very sick with diarrhea and painful cramps in my stomach. I really needed to go to a doctor, but they didn't care. I wanted to leave and go back to Nadi, but their boat was already gone and I've been told to don't take the SSC cruise cause it's too expensive (160 Fijan dollars), after few more hours I couldn't resist the pain and I had to leave...they took me and my girlfriend back to Viti Levu for 200 dollars even if we had already paid the transportation for the way back.
When I felt better I wrote an email to David, the guy I paid at the time of booking, to ask him a refund for the 2 nights and the boat we didn't use. He said he doesn't handle money so I had to ask directly to staff manager on the island. Well I called him and he said to talk with David...nobody wants to refund us, they still owe us 368 Australian dollars.
Mana Lagoon backpackers shouldn't be in any travel guide, it's your worst choice in Fiji, DON'T GO THERE !!!!
Enrico

Why don't you contact the Fiji Tourist Bureau or another tourist-oriented establishment in Fiji? Even the Fiji Times. They might not be able to get your money back, but bad publicity might make someone sit up and take notice.

I stayed at this place on Mana 2-3 years ago and found it fine.
No hole in the roof, OK food (for the price), all guests perfectly happy.

Transfer was cheaper than on the regular boats, and accommodation with food cost a pittance at FJD 60 for 3 nights!

My impression, based on the fact that you talk of AUD, is that if anyone ripped you off, it was the (Australian?) agent you booked through.
He probably sold you the accommodation plus transfer package for a lot more than the owners on Mana actually got, so it would be unrealistic to expect THEM to refund you the money which was almost certainly mostly pocketed in by that David guy.

Who is David? Is he at the resort, or somewhere else?

Just like in life, you get what you pay for. Lesson learnt.