As someone who's done about a year in jail, total, and beat 3 prison felonies, and knows a bit about lock up, I can tell you that those protection yards are called PC, or SNY (protective custody or sensitive needs yards.)
They house cops, chomos, and the like, but here's the thing: they also house gang dropouts.
And a lot of those dropouts and snitches, believe it or not, start new gangs ON the PC yards, like the Pesetas or 25ers, Against the Grain, 187 Ride or Die, FTS, Northen Riders, and a bunch more.
And those cats go right back to gang banging, so it sure wouldn't be hard for the dude to get touched, even there.
And THAT'S if he's lucky enough to be in a state that even HAS ANY pc. Some states don't. They just throw you on the mainline with everyone else, and you get extorted and such.
So what do you guys think will happen here? AGain, I'm betting 10 to 1 he BEATS the murder charge, and does 2 or 3 years on the manslaughter