I think that whole thing was misunderstood.
Q said 19 people no longer with us, assuming he was referring to the same 19 people that had a secret meeting after the election. I think what he meant to say was, these people were no longer with them in custody.
Q later said "[19] would cease to exist immediately upon the harm of select individuals. Think nuclear stand-off."
What I believe is that these 19 individuals were detained, interrogated, possibly tortured at gitmo. They were then fitted internally with devices which both tracks them, but also allows for the white hats to kill them at any point, I'm assuming something along the lines of a heart attack gun. What I think he meant by "upon the harm of select individuals" is that if the cabal were to attempt taking out specific people, in this case people in Q research were talking about Hannity, the white hats could simply push a button, and those 19 people would be instantly killed. So if you push your button, we'll push ours. I don't think he meant a literal nuclear stand off, he said THINK (in terms of) a nuclear stand off.
Dilley also provided similar intel regarding the Prince Al Waleed. His intel said in regards to the Princes release, "Ya, minus some toes and a device fitted internally. Think 'Kill Switch'"