"under the cover of night" just means after 20:00 but before 0:05 in game time lol. and yeah, but rereading your last thing, have you done the thing where you explore the cave with Scar alone? because if you haven't my bad I completely misunderstood where you were. and the option should show up at the cave as "meeting point"
and no one has met yet her lol. she's just spoken a lot about by over half the NPC's in game involving Northcrest XD