Namgem was equally owned by the state and Lazare Kaplan International, a company owned by Templesman, an American diamond merchant.
The Namibian newspaper reports that Namdia had bought into the loss-making diamond manufacturer despite lacking the technical capacity to run the factory.
Namdia also passed on the management of the company to an unnamed Indian company as a technical partner.
"Namdia presently does not possess the skills and abilities to run a diamond-cutting factory. In order to de-risk the operation, so as to not incur potential losses, a technical partner was appointed to operate on own account and at own risk," the company was quoted as saying.
Namgem, which is chaired by Namdia's chief executive officer Kennedy Hamutenya, had been posting losses in the past four years and was bailed out by shareholders.
Namdia had since June 2019 bailed out Namgem with about N$5,5 million.
"We did not want the company to shut down entirely, and jobs lost, so we approached Namdia to buy the other half," mines minister Tom Alweendo was quoted as saying last month.
"This was the reason we approached Namdia; maybe they can turn it around."
Mathew Nyaungwa, Editor in Chief of the African Bureau, Rough&Polished