He is now on bail with strict conditions, including surrendering his passport, and living in the capital, Nairobi.
He was due to return to court yesterday to face allegations he stole equipment and gold from a mining company in Narok County that he had travelled from Japan to get involved with.
If Strange is found guilty, he faces seven years in jail.
Originally from Paeroa, in Waikato, Strange emigrated from Ponsonby to Australia in 1981.
The last contact his family had was in 1990, when he was living in Sydney. He moved to Tokyo in 1992.
"I love my family. But my family is a little conservative. I wanted to do something where I could make a major difference," he said from his Nairobi apartment.
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A fortnight ago, his mother, Liz Simpson, received a call from him at her Bay of Plenty home. "We'd all assumed he was dead," she said.
Fearing the contact was part of a fraud, Mrs Simpson asked her other son, Gerard Strange, a Waihi farmer, to check out his story.
"We hadn't heard from Francis for nearly 30 years," Gerard Strange said. "To get this out of the blue, we thought it was a scam.
"I talked to him and tried to ascertain, through asking some questions that only he'd know the answers to. I said to him, 'We don't know if this is you or not. It could be any English-speaking person, really.'
"He sounded very calm. It was almost an everyday talk. I guess the difference was so many years going past, and me trying to pick was it his voice.
"He said a couple of things that I'd forgotten about, too, and so I rang my mum back and said I was pretty sure it was kosher."
Since then, Francis Strange has emailed his estranged family lengthy correspondence about his case.
If he wins his court battle, he plans to stay in Kenya and plough ahead with plans to develop a mine extracting minerals, including manganese and iron ore.
"Everybody knows that Kenya needs investment. Kenya needs jobs. There's a lot of people who want to see this happen. But it really is dog-eat-dog here."
His vision is for a massive mining and industrial city in Taita-Taveta County, in the southern tip of Kenya. It could generate between 300,000 and 500,000 jobs during its construction over the next decade, Strange said.
In April 2014, Strange took legal action against Mboe Sambu Resources, seeking a restraining order on their activities, claiming it was operating without a licence. Nine months later, he was arrested alongside Australian friend and business associate Stephen Samuel Paino and charged with breaking into the mine and stealing equipment and gold worth $630,000.
Both vehemently deny the charges. Paino has since returned to Sydney.
In Wellington, a spokeswoman for the Ministry of Foreign Affairs and Trade said it was made aware last year of Strange's arrest and detention and continues to give him consular assistance.