Using the freeware utility, reactor StickLay, you can fix the layer for selected DWG drawing objects. This way, the objects will always remain at their current layer and cannot be moved to another one (if the StickLay utility is loaded and enabled).
Download StickLay from Download and load the VLX file into AutoCAD - e.g. using APPLOAD, dragging the file onto the briefcase icon. Then type the STICKLAY command and use its Stick option to select objects to remain "stuck" (glued) to their layers.
Use the Unstick option to "unglue" them from the layers again. The On and Off options turn the layer watch reactor on and off. Use the Show and Showall options to list the current assignment of objects to their fixed layers.
The Quickmode option (toggle) limits the layer watch reactor just for output commands (Plot, Save, Export, WBlock, Regen...) and for commands that potentially change object layers (Change, ChProp, LayMch, Layer, AMlayer...).
See also the FLAY reactor for forcing layers by object type or blovk name.