The pivot to a lighter Thor - the Thor you see joking around in the Avengers movies - gave Marvel the opportunity to bring Waititi on board.
Thor: Ragnarok producer Brad Winderbaum told news.com.au he immediately thought of Waititi because What We Do in the Shadows (the quirky vampire mockumentary the Kiwi made with uni mate Jemaine Clement) had just been released.
"Then when I showed Boy to [Marvel bosses] Kevin Feige, Louis Esposito and Victoria Alonso, it was very clear to us that this could work and that this guy could be it - his characters have a lot of humanity to them."
Before Thor, Waititi's biggest hit was last year's masterpiece, Hunt for the Wilderpeople with Sam Neill (who cameos in Thor). It broke Kiwi box office records and played a not-insignificant part in the director being named New Zealander of the Year for 2017.
He's also directed episodes of Flight of the Conchords and popular videos including the Air New Zealand Middle Earth safety video and a clever anti-racism plea. He was nominated for an Oscar for his short film Two Cars, One Night and even took an early pass at the screenplay for Moana.
The key to Waititi's success is his sense of humour - a laid-back, sometimes-deadpan, always-hilarious sensibility that Australian audiences will recognise.
"I feel like I know what is funny," Waititi said. "And there are definitely people out there like me who think the same way. With the story, I would suggest things or throw ideas in that I would like to have seen in the film."
While Waititi usually writes and produces his own films in addition to directing and starring in them, here he took a few steps back, relinquishing those reins.
"I enjoyed giving up a bit of control because it meant I could concentrate on other things," he said. "Usually, on my smaller films, I'm doing everything, like carrying trays of food around for people.
"No matter what film you make, it's all exhausting but on this one, it was nice to have someone else writing, someone else doing the organisation so I could focus on what I'm shooting, the jokes and what we're doing with the actors. It was a really freeing experience, actually."
Waititi may not be credited as a screenwriter but he improvised most of the film's dialogue on set.
"It felt like 80 per cent, it felt like we were just making that entire thing up as we were going along," he said. "If it was really specific dialogue or exposition or dramatic, we wouldn't do it as much. But on the other stuff, we could be a lot looser.
"We would improvise vastly different versions of the scene - anywhere around 10 different versions of the scene, on average.
"I gave everyone permission to kind of enjoy themselves and throw any idea into the ring. If it was a good idea, it would stick, if not we'll keep trying. I think people are too worried about failing or having a bad idea. Most of my ideas are bad. You have to push through them, it's better to try them and you find gold. It's what keeps the filmmaking process fun."
One of those "gold ideas" was Chris Hemsworth's concoction of the "Get help" gag with Loki to liven up a rote shoot-em-dead sequence.
You may not expect an idiosyncratic New Zealander known for his heartwarming indie movies about underdogs to end up in one of the biggest corporate machines in Hollywood, Disney. But his experience seems have been relatively smooth.
"The good thing about Marvel is that there's not many of them at the top, there were only three or four people I would answer to," he said. "If you're on the right track with them, they can give you a lot more freedom and allow you to be a lot more creative. I think it's when you resist that working environment or method that you run into trouble."
Not every director has had an easy time with Marvel. Avengers helmer Joss Whedon famously walked away from the franchise after Avengers: Age of Ultron, declaring himself "beaten down by the process," some of which he credited to conflict with Marvel.
Thor: The Dark World director Alan Taylor came out two years after its release and condemned it as a "wrenching" experience he wouldn't wish on anyone else and that the movie he filmed wasn't the one that came out of post-production.
Winderbaum, who rose through the Marvel Studios ranks to become vice-president of production and development, said: "Every filmmaker's process is different and every relationship is different.
"On Thor: Ragnarok, we had a really wonderful, collaborative environment. Taika understood what he was getting into with the Marvel Cinematic Universe, he understood the overarching narrative. He had fun playing in the 'sandbox', as he called it.
"All the characters tie together in a single universe, they share continuity and an overarching story. It's fun to be able to use a different lens to peer into that narrative and each director has their own vision and their own tone.
"Taika really understands character and he understands human conflict, whether it's for comedic or dramatic purposes in a way that's fundamental. It's part of his process and it's part of his vision for the movie."
Waititi appeared to have impressed the bosses at Marvel, not just because he got to inject so much of his style and tone into Thor: Ragnarok but also because Feige is "confident" the Kiwi will be back with Marvel before long. In turn, Waititi told RadioTimes he would be keen to work with Marvel again.
With Thor: Ragnarok about the open around the world over the next two weeks to glowing reviews (its Rotten Tomatoes score is currently sitting at 98), the Maori director's stock is about to rocket. His name is now uttered alongside compatriots Peter Jackson and Jane Campion.
Of course, his next project looks to be as offbeat as you'd expect: a stop-motion animation that expands on the affinity for Michael Jackson present in Boy by focusing on the late pop star's chimp, Bubbles. Netflix reportedly bought the movie for a rumoured US$20 million.
In the meantime, Waititi will have to contend with the super fandom that comes with any Marvel movie. He said he's not quite prepared.
"I'm lucky in that I'm not recognisable in the film. [My character Korg] is just a pile of [CGI] rocks," he said. "As a director, I don't have to deal with that kind of thing, which is quite nice for me. I still retain a degree of anonymity. If possible, I would like to keep that."
Thor: Ragnarok is in cinemas now.