Yes. Key to passive is that when detached the end effector may not move or perform functions on its own. In other words, you may not drop off a little car that moves around the field on its own to move an object. It also should not have its own stored source of energy.
Completely supported means that ultimately, the weight of the object is transferred to the playing field only by passing through the egg carton. So if an end effector, other object etc is itself fully supported by the carton, another object fully supported by one or more other object fully supported by the egg carton is considered supported by the egg carton even if it does not touch the egg carton. Note, if this interim object is supported by two egg cartons, any object supported by it is NOT fully supported by any one carton and would not be scored in a carton.