"It's a stitch-up. I never saw the merchandise they're accusing me of," the 53-year told RFI's French service.
"The company Cajaf Common that I was managing never saw the drugs, because the container seals were tampered with. Furthermore, we were taken to court after being held in custody for 8 days, and the court finally cleared us."
In 2016, maritime police discovered the haul at the port of Cotonou in a container destined for one of Ajavon’s companies.
The business tycoon has always denied charges of drug trafficking and initially was cleared of any wrongdoing.
But on Thursday, he was charged with "high-risk international drug trafficking" of cocaine worth an estimated 16 million dollars, or just under 14 million euros.
The case against him has been reopened "because one of the partners are not satisfied by the first decision," explains Urbain Amegbedji, head of Benin's national employment agency.
Yet his legal team have denounced serious irregularities in the process and censorship by the authorities.
"When we arrived, the court prevented us from speaking," Marc Bensimon, one of Ajavon's lawyers told RFI. "We were all gagged, and weren't allowed to say a word. In their view, as lawyers, we are unable to speak if our client is not present. This is totally unacceptable and an infringement of the rights of the defence," he said, vowing to fight the decision in a higher court.
Ajavon did not appear at Thursday's hearing in the capital Porto-Novo, saying he was advised by his lawyers not to do so.
Friends and foes
"Everyone knows that I've never been afraid of facing the justice system of my country, as long as it's independent," he told RFI. "But when it’s not, what's the point in going? I can't risk putting my life in danger."
"The justice in Benin is independent," retorts Amegbedji.
"Why did he not show up? The same justice relaxed Mr Ajavon in 2016, the same justice can relax him in 2018," he says.
Yet the landscape has changed since then, notably relations between Ajavon and President Patrice Talon have soured.
Ajavon came third in Benin's presidential election in 2016, and threw his weight behind Talon to help him win the second round run-off against the then-prime minister Lionel Zinsou.
"We made a huge mistake in electing Mr Talon as our president, and I think the public will let him know," he comments.
In March, Ajavon launched his own political party with a view to another run for president in 2021. Ironically, his legal woes are actually making him more popular, he says.
"The more my legal woes grow, the more support I receive from the people of Benin."
Currently in exile in France, the man dubbed Benin's "chicken king" from having made his living selling livestock, insists the "real culprits" who stashed 18 kg of cocaine in one of his containers should be found. "We need to find the people who did this."