The workers had accused her of financial mismanagement and high-handedness, which led to her suspension.
The Federal Ministry of Health had on Wednesday reinstated Uwakwem, saying her appointment was a presidential issue that can only be reversed through the same channel.
Uwakwem had a running battle with the labour union at the centre that accused her of financial mismanagement and high-handedness, which led to her suspension.
The Ministry, however, said since no evidence of misconduct was raised against her by a Ministerial fact-finding commission, the medical director has the right to finish her four-year tenure which will end in 2017.
Upon learning of her reinstatement, the workers reportedly locked up all offices, medical units and wards in protest, accusing the Minister of State for Health, Dr Ehanire Osagie, and the Director of FMCs, Dr Ngozi Onwudiwe, of facilitating the return of Uwakwem.
The aggrieved workers said the director has a case to answer at the Economic and Financial Crimes Commission (EFCC), stressing that she should go and clear herself of the charges against her first.
"We won’t allow someone who has a case with the EFCC to be the CMD of this centre. She should go and clear her name of the financial allegations levelled against first before she could come to struggle to be CMD," the workers said in a statement.
Responding to the drama, Uwakwem said she has been cleared of any wrongdoing by the Ministry of Health, on which basis she was reinstated.
She said as long as the Federal Government is not in doubt of her integrity and competence, the workers' allegations is nothing to worry about.
"I am not even in Owerri now. They are just lying against me as usual. The truth is that I have been cleared of any wrongdoing and I have been asked to resume work immediately. I am the chief exectutive; I can resume work from anywhere," she told Punch on the telephone.
"For now, I have resumed work, but I’m not yet in the office; the order was with immediate effect. They should let the court decide; you don’t say somebody is guilty until the court says so."
The Police Commissioner, Imo State Command, Taiwo Lakenu, said since the government has directed that the CMD resumes immediately, the workers have to obey that authority.
He said policemen will ensure the CMD resumes without any hassles or harassment from the aggrieved workers.