For G-5 artists it's more that they don't really like to follow steps, because it would give the person that performed a x place more "power" and them being labeled as 'followers' of the 'guide' compared to G-4 artists who wanted to prove that they "corrected" the show or had a bigger crowds. Look how Heritier wanted to perform for years at Zenith, but changed it, when seeing that Fabregas planned as show there and his manager David Monsoh wanting to let him perform at Adidas Arena, but him not wanting it, thinking that people would say that he followed the steps of Ferre Gola who he sees as rival. Which made him wanting to plan a perfomance at Bercy, but when getting informed that there was a new hall opening in Paris' suburb Montreuill, he wanted to plan his show there. By planning a performance at La Seine Musicale he felt like he's equal then Ferre, who was the first at Adidas Arena.
For Werrason, I don't maybe. Maybe he felt to big seeing young gospel artists now performing at Zenith, maybe it's someone in his staff who contacted a concertpromoter to get him at Arena Grand Paris, to show that Werrason is the elder and not entering the polemic around following x or y at Adidas Arena & U-Arena and Werrason just accepted the offer, since it's his job.