A state lawyer found the claims to be suspicious though, Kenya's The Star newspaper has reported.
"There are no medical notes to support the report and on January 30, Strange took it upon himself to have a matter before court published in a national newspaper, just a few days before he was required to appear, to sway the public for unnecessary sympathy," the lawyer reportedly said.
An arrest warrant has now been issued, it is understood.
Strange, along with Australian friend and former business associate Stephen Samuel Paino and Irishman Michael Lynch, has been charged with the alleged theft from Mboe Sambu Resources mine in Narok county on May 24, 2014.
The Star reported that the trio are accused of stealing mining equipment, heavy machinery and tools, as well as generators, a ball mill crusher and rods, a concentrator, four tool boxes, as well as processing chemicals, and "10kg of gold concentrate".
Last week, Paino told the Herald that both he and Strange have been set up.
Paino said he wasn't even in the country at the time of the alleged 2014 theft.
"I haven't been in Kenya since May 2011. But I have been charged for, a minimum of what I know, could be more, two crimes," Paino said from his home in Sydney.
He claims that both he and Strange, who he first met in 1990, have been set up.
Paino said he had grave concerns over his friend's safety."I fear for his life," Paino said.
He refused to comment further about the case.
Strange had been on bail in Kenya's capital city of Nairobi.He told the Herald earlier this month that he was innocent and was preparing to defend the charges that carry a maximum sentence of seven years in jail.
Strange moved to Kenya from Japan, where he was an English language teacher, in January 2014 for a business venture in Kenya's mining industry.
But a few months later he took legal action against Mboe Sambu Resources Ltd, seeking a restraining order on their activities, claiming it was operating without a licence.
In January last year, he was arrested and jailed at Kisii GK Prison, where he was one of only two white prisoners.
He says he was twice attacked in what he called murder attempts.
The Ministry of Foreign Affairs and Trade says it was made aware last year of Strange's arrest and detention and continues to give him consular assistance.
He has not responded to fresh approaches from the Herald.
For the first time in nearly 30 years, Strange last month phoned his mother in Bay of Plenty who told the Herald: "We'd all assumed he was dead."