I think I had said this in the previous chapter that weak link like this might break his team but Ness is different because he is the genius that help Kaiser rule the BM team that is why Kaiser evolved so much after leaving him behind. Ness is differently one of the strongest players in the BM team, to change all he has to do is embody a flexible ego mindset and evolved to his own foot ego. 
I think I get is now, what Ego as talking about all this time about how the environment changes a person, because Ness and Kaiser where use to a football where Ness evolves just enough to be of the best assistance to Kaiser and Kaiser evolves more to become the bast in the world but the blue lock environment forces one to think that if you are not ready to give it you 100 and 10% in the field and reliance can be a weakness and also a opportunity to further growth. But I believe Isagi has seen the great potential of ego growth in him and he is going to take it and I think Kaiser also know that Ness has great potential in him and to reawakening it quickly he has to use a reverse psychology on him and force him to grow, if Noel use Isagi to evolve Kaiser then he might use himself to evolve Ness for his own goal or maybe Kaiser is an even bigger psychological genius by not only fooling Ness to growth but also Isagi, making Isagi think that Kaiser miss out on a potential player like Ness and he was going to evolve him for his own goal but in reality, right after Ness evolves,,, he can help Kaiser get the ultimate goal that will get him the sit at the world stage. I mean Noel did it why couldn't he 🤷 or it might just be me over thinking it.