Stone was a solid weight, a shield for the Guard as much as he was able, built from the stone that he was named after. And if he didn’t have that, what did he have, in the end?

Sometime between the end of the war and when Fox got shot, Coruscant Guard CMO Basher got their hands on the good drugs. That was the only explanation, really. Someone (Thorn) also made the mistake of giving Fox a datapad.