What the law says: civil marriage first
Ivorian law has constructed a model whereù the state confers legality of marriage, in particular via the Marriage Act of 1964. In this context, polygamy is frequently presented as prohibited since the 1960s. Result: a “customary wife” can exist socially, but her legal status is not that of a wife in the civil sense (principle, to be qualified depending on the situation).
Polygamy vs adultery: two different debates
Say “he was married’ customarily at she” is not enough to prove legal polygamy: if the law does not recognize customary union as civil marriage, we are not talking about the same legal object.  On the other hand, if a person is civilly married and maintains a lasting relationship outside of marriage, this may fall under marital fault (divorce for fault) and, depending on the applicable texts, under the criminal concept of adultery.  Here, everything depends on the established facts (relationship, duration, evidence) and the version of the law in force at the exact moment.
When the public narrative “complicated” : protocol and legitimacy
The most sensitive point is not only legal: it is the public scene. In many systems, the “First Lady” is linked to the status of legal spouse of the head of state. If another woman appears as a companion during trips presented as “official,” the debate shifts: protocol, symbols, respect for institutions, and political reading of private life. This narrative can also blur the lines: what is “customary” in society is not automatically “official” in the state.