Add rig to mesh attached through socket

I have a pair of handcuffs that I put on a dead NPC character. By design the handcuff only goes on one hand since the other side is attached to a key that dangles from their dead hand.

I created the handcuffs and the key as a separate static mesh and attached them to the NPC mesh using their BP and a socket that I created on the NPC skeleton. However the handcuffs are obviously rigid and don’t have the same skeletal ragdoll as the rest of the body. So I want to add a rig/skeleton to the handcuffs+key. Should I just create that in Blender and update the static mesh component to the new rigged one and expect it to work as it is?

No one knows how to use sockets in this way?