Zombies

Why didn't Gecko Moria ask sen goku to be allowed to steal the shadows of impel down's inmates.

The criminals are unable to left the dungeon or they die. When their execution day arrives. Moria would release person's shadow.

After Kaido is defeated, Blackbeard will come to wano and finish him of. With his new tenth titanic captain Gecko Moria, he will steal his body to turn into a zombie and put some powerful persons shadow in it to create the strongest Zombie ever spawn.

I feel like I remember a segment but I can't seem to find proof of it anywhere. I don't really remember much of it but from what I do:

Luffy and Co. slide past enemy lines and enter into this tower to challenge a floor that grants power over part of the sea (what exactly the floor gives I can't remember). But they end up running away from the navy and end up on one of the floors by accident and have to fight zombies from Thriller Bark because they have control over two of the floors. Does anyone remember this or am I losing it?