Y'know, I just had two ideas about Flamingo's ability.
1. We only saw him controlling two people, and they could still speak, right?
What's connected to both? That's right.
SWORDS.
What if his controlling has contidions? For example, he can only control two people with both hands while at least one has a sword he uses. The advantage is to neutralize DF power, perhaps? We saw BB having one of that kind, and he said that one was exceptional among LOGIAS. Plus, Flamingo's power might be kept in secret, it is a nice one if not known beforehand [not bringing a sword].
But hey, Zoro has a sword at his mouth too.
If it's like that, I say Oda's foreshadowing surpasses every single human in mankind.
2. A Paramecia version of Enel's DF.
We still don't know if there could be different versions to DFs. For example, a Logia wax [Mr. 3] or Paramecia claws [Any Zoan with claws].
If it could be true.. Flamingo might be producing electric waves from his hands to control the nerves.
That means he can control the brain, but did it from the neck down because he found it amusing or something. And that means he can control as much as he mastered his DF.
Hey, it DOES work with what we've seen.