Ironically a "lights going out" marker wouldn't work because the AI couldn't see it, because it's in the dark (IIRC). But I think the torch & light "should be on" flag works by ... well I don't remember exactly. Better to go straight to the source code than try to speculate.
Edit: I don't think they cue an alert change anyway. For a torch, they cue the AI to mumble and relight it.
Edit2: I should have looked at the link you posted first. I was talking about the "light should be on" flag, which might work for this too if there's an electric light version. That link is for a "it's broken" flag, which as the link describes it is in the stim/response system. In that system, a broken item is going to give off "vis" stims, and if an AI "receives" the stim (by seeing it), then its alert rises. That is, it's not a marker-creating class at all; it's in the stim/response system, which objects carry in their properties (IIRC).
You'd want to do testing to see if / how it works in practice if you really want to use it.