Maesaiah, who was married to Lesotho Prime Minister Thomas Thabane, had been in hiding since mid-January after police called her in for questioning over the killing of Lipolelo Thabane.
On Tuesday, Thabane turned herself in and appeared in court on Wednesday in handcuffs and under heavy police guard.
The court said she has a right to apply for bail, but deputy police commissioner Paseka Mokete said the police would object to any bail application because she had fled the country.
The prime minister’s previous wife was killed in June 2017.
Maesaiah married the prime minister after the death of Lipolelo, and right before he began his second term in office in the small African kingdom that is completely surrounded by South Africa.
The prime minister and Lipolelo had been in a drawn-out divorce battle while he was already in a relationship with Maesaiah.
The two women battled each other in court over who should be the legitimate first lady, with the judge ruling in favour of Lipolelo.
Maesaiah has also been charged with the attempted murder of the woman who was travelling with Lipolelo when she was shot dead.