I always thought it was Soleil but I did find it strange that he had two vocals in the song. But it does make sense if it’s Arca because he’s credited on the album but I always thought he had his vocals deleted like Asso, Mirage did due to Modogo and Bouro’s return but if that’s the case then why didn’t Koffi delete his vocal but deleted Asso and Mirages? most of Brigades vocals got deleted too except for his part in the generique but that was only because his cries was featured in the Boma Nga N’elengi bonus and it became popular.
About Koffi erasing Mirage and Assow’s vocals, I think it had to do with Modogo and Bouro rejoining Quartier Latin. Mirage left Quartier Latin very early during the Europe tour, he only did four or five concerts before leaving. Bouro rejoined towards the end of the tour (Koffi anticipated Fally's upcoming departure) and took part in their last concert at the Élysée Montmartre. Meanwhile, there was still no sign of Mirage, who had disappeared from the radar. Koffi probably assumed that Bouro would stay for at least two more years, so he likely decided to replace the vocals of someone who didn’t take his work seriously with those of Bouro.
About Assow’s vocals being erased, it could be that someone in Kinshasa gossiped about him through the phone, claiming that he tried to join Maison Mère. Back then, Bibicia and later also Patience and Brigade joined Wenge Maison Mère after being left behind during the Europe tour. Accoring to Ferre, when Koffi was furious, when he heard through the phone that Patience joined Wenge Maison Mère in Kinshasa (It's a shame that 2eme soin never came lol).
Another possible factor is that Koffi has a lot of respect for Modogo as a singer. Koffi praised him several times publicly. By the time Modogo officially rejoined Quartier Latin, the album was already almost completed. However, Koffi decided to release it the following year and releasing Boma Nga n’Elengi in the place.It could be that he wanted Modogo to be part of the project and for these reasons decided to erase Assow’s vocals, because Assow still being a rookie at that time.
Thinking about Arca Dineiro, I believe that’s the reason he mentioned his own name in the song Salopette during his vocal (Btw, Soleil used to sing the last part of that vocal during concerts). Despite that, the vocal being a succes like the others vocals in the song and him appearing the videoclip, he still had the bad luck of most people not knowing who he was, while Quartier Latin was slowly turning into Quartier Cindy
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