The top group with old leaders at their guidance Wenge and Quartier Latin are leaded by two guys who accomplished everything, Werra basically fueled the Congolese scene with 100% of musicians came out from his group without Fally (by the way he was tested by Werra but Werra didn't took him, so let's say 100%) with Fally also loving Wenge style, has been the main reference for live concerts until Mayi Ya Sika and Malewa and Koffi a guy who basically reached the peak with V12, Tcha Tcho style and many others memorable songs and album who became legend for African music and not only Congolese scene.
They don't feel the need to keep guys always confronting with them for few reasons.
1. Control
They understand how powerful control is and a group well united is more tasty to the public
2. They Think They Know.
Since they have already accomplished many things many times they feel that they will do everything good in fact Werra failed big time with Bercy being the number one Atalaku in Ingeta leading Fleche Ingeta (ex-Fleche India Ezui Ezui) to being a big fail except for Kata Fumbwa, Lobeso's Crie Musselu, and Bercy Mwana praise to Didi Kinuani despite an excellent guitar from Makaba.
Werra wonderstood that and gave Ambulance the key to the atalaku section putting new fuel with Goldberg (who had limited space in generique but did excellent) and the surprising Anti-Balle leading 7 jours to being a success from the point of songs equal as Kibuisa Mpimpa, the same for Koffi after Mutshibara who was a big flop, Koffi wonderstood the lesson and came back to life with Selfie, which has been credited as a stupid song but it was one of the most successful song in Africa leading to Drogba dancing it in Canada.
So they feel untouchable, when they make a mistake they do everything possible for avoiding it, for example Werra will not have problems to talk about Fabregas, calling back Adjani for some visits or Deplick, but he rarely speaks about Ferre, Heritier, and Bercy since their departure especially Bercy do you remember in a Zamba Playa rehearsal when Lobeso was singing how well he was received, randomly after Bercy's departure, Koffi rarely talk about the failed album he had when he started his career, or the mind games he plays for fucking up rivals musician's life but he will be sweet as candy with Fally or Brigade while he doesn't leave any occasion for speaking bad about Ferre.