mj_set_mocap and mj_set_onebody do not move objects in the environment. After setting a new position, the change in position reflects itself when mj_get_onebody or mj_get_mocap are called, but the hand doesn't move within the VRE. I am using MuJoCo HAPTIX v1.2.
Sorry, false alarm. I had two instances of MuJoCo opened and was looking at the wrong one (doh!). mj_set_onebody and mj_set_mocap work just fine!