Imitating a Progenitor's speed can be considered, absolutely dangerous for those that are very far from it...
Blake had really overestimated himself, his almost shattered body trembled in pain after that immitation, and still he wasn't able to break through that Speed.
Normally, once he has copied a speed, it is very natural for him to adapt to it. But today, it was as if his mind became breached, leaking away that information from his brain, lost forever.
The only way out is to immitate again, but after realizing what that same speed had done to him, he did not try it again.
Luckily for him, that same speed had enabled him cover a great distance away from the Progenitor, telling that the speed he copied off was far more superior to a Divine-progenitor's speed, and it was surprising that his body was able to endure such speed.
An hour later, the hidden region that was separated from outside of reality became compiled with Blake's team.