Lucifer probably could. Shining Armor never actually sang in the show from what I heard.

Cadence wasn't sure whom Lulu was talking about, but even without her powers she was sensing massive red flags. Still, it'd be best to ask for clarification before making a judgment call and potentially going full aggressive towards the poor mare...female human...female demon (did either of those have special names?) should she ever show up.

"I'd think that if she ended up here she'd be more relieved to see that you didn't disappear because you wanted to since she'd have just gone through the same thing. Pretty sure Shiny would feel that way if he ends up here, too," she said, carefully lifting her cider glass with her hooves to take a sip. She then chased it with a longer sip of her water. "So who is this person? Maybe I can keep an eye out in case she shows up and help her find you."