Widely mocked plans to establish a tropical haven for cryptocurrency enthusiasts have run into trouble after a contract to buy an island in Fiji for US$12m fell through.

A group of crypto-evangelists, led by Max Olivier and Helena Lopez, outlined plans for the island, Nananu-i-cake, in a lavishly animated YouTube video, featuring a wide-eyed crypto bro named Christopher landing by helicopter and being given a guided tour by a talking coin called Connie.

The full YouTube clip has been taken down, but cached copies show it touted the island as “an international hub for the community to come live, work and have fun and enjoy a first-class crypto lifestyle”, boasting “a complete ecosystem that represents the blooming crypto space” that was “a paradise made by crypto enthusiasts for crypto enthusiasts”.

Areas planned included Cryptoland Bay, Crypto Beach, House of Dao – a reference to decentralised autonomous organisations, a form of non-corporate structure promoted by crypto enthusiasts as an alternative to companies – and the members-only Vladimir Club, another crypto in-joke that refers to people who hold 0.01% of a given cryptocurrency.

Also on offer were 60 plots of land on what the video describes as “the Blockchain Hills” (Nananu-i-cake has only one hill). These were to be sold to “Cryptolander Kings” via non-fungible tokens – unique tokens that use the same blockchain technology underpinning cryptocurrencies like bitcoin.

The project has been compared to the collapsed Fyre festival and the 18-minute video was greeted with scoffing on social media.

There was also controversy after the Cryptoland Twitter account responded to a question asking what the age of consent would be on the island with a now-hidden tweet saying: “Mental maturity should be more than enough! ;)”.

The actual age of consent in Fiji is 16.

Cryptoland apologised for the tweet, saying it was a misunderstanding due to the fact its Twitter account was run by several people, not all of whom “spoke English as a first language”, and they thought the question was about age requirements to visit the island.

But the project appears to have hit a bigger hurdle than bad publicity. The real estate agent selling Nananu-i-cake, Rick Kermode, of New Zealand firm Bayleys, told Guardian Australia that the contract to sell it to Cryptoland’s backers fell through this week and the island was back on the market.

“We’re telling people that it was under contract during the period of time that they had the contract but it has come back on the market,” he said.

The 220ha (550-acre) Nananu-i-cake sits about 1km off the northern coast of Viti Levu, one of Fiji’s two main islands, about 2.5 hours drive from the international airport.

According to Kermode’s listing, it offers a jetty, five beaches and a luxury villa (with a pool) that sits on one of the island’s highest points “with magnificent 360-degree views, most particularly to the west over neighbouring Nananu-i-ra and the south Pacific Ocean”.

Kermode said it was a fantastic site for tourist development because it was on the eastern side of the island that gets the least rainfall and is available for sale on freehold title, which is rare in Fiji.

Tourism development on Fiji had been hit hard by the Covid-19 pandemic, he said.

“It’ll probably start to happen again, hopefully when tourism starts to regenerate itself,” Kermode said. “Covid has been a big problem for everybody.”

Guardian Australia could not reach Olivier or Lopez through Bradley Robinson, whom Cryptoland describes on its website as its project manager.

However, during a YouTube interview with crypto-evangelist Kyle Chasse, who claims to have bought one of the island’s plots of land, Olivier said Cryptoland made the animated promotional extravaganza because “it’s the only way you can feel what Cryptoland is”.

“We tried to explain to people the vision but you realise that words just get so limited,” he said in the video, which was uploaded on 15 November.

Speaking about the process of buying the island and transferring plots to “King Cryptolanders”, he said: “In the coming weeks it will require to do some paperwork, of course, transferring ownership.”

Robinson said the company where he is chief executive, Raffe Hotels and Resorts, had “expressed interest in being involved in the Cryptoland project”.

“To date, I have been involved in an advisory capacity during the master planning process, assisting the founders and architects with concept development,” he said.

“At this stage I have not formalised any arrangements with the developer to play an ongoing role, however I am continuing to discuss various project management scenarios with them.”