Hitting same wall.
I replaced the ensureMsg with a log, but that led a bad child index in USceneComponent::OnComponentDestroyed().
Through in a check for that to prevent it.
Now, when I detach the affected component it detaches several other components that were spawned client side.
Server side, the affect component does not share the same owner or parent component as those that will be spawned client side.
Client side, the bug causes the affected component to have the same parent as those spawned client side when it detaches (apparently).
Very confusing 