Kinematic Output on Envelope Deformer

Is it possible to attach a kinematic output node to curves in an envelope deformation chain?

Suppose in the attached image, I wanted to bind the offset joints of arm_1, arm_2, and arm_3 to Offset, Curve, and Curve_1 respectively so that as Deformation-Body animates and those curve points transform, the roots of the arm joints would follow the contour of the body drawing.

I’ve tried adding a Kinematic Output node to those layers via the timeline view, but it tends to do weird things when a KO is attached to a curve node of a deformation chain. When the KO is attached to the Offset Node of the Envelope Deform, the entire chain seems to disappear.

I was able to have some success by using a simple bone chain running through the center of the body. Bones were added via timeline view and NOT rigging tool so the bone nodes appear OUTSIDE the deformation node. The only way I was able to bind child deformation chains to parent chains was in this manner: parent chain consisting only of bones added via timeline, and child chains connected to each parent bone with KO node. Is this the only way? Can KO nodes be connected from parent nodes INSIDE a Deformation Chain Node to children OUTSIDE that node?