Replicants aren't androids, they are just clones made using the DNA of the Gestalts. It's also not ash they turn into, but rather salt. Some of these salt creatures stay alive to form the Legion who fight against what's left of humanity.

You're also completely off with what black scrawl is. Black scrawl is what happens when a gestalt relapses losing consciousness and becoming aggressive. This causes the genetic material the cloned replicant is made from to break down. Once a gestalt relapses it can no longer inhabit a replicant and will eventually die. The scientists and androids were trying to prevent relapse, that's the entire fucking point of the original gestalt (Nier/Shadowlord).

Someone hasn't actually read any of the law, because almost all of this is wrong.