Do you think Slick will just outright explain to them what's going on, then? If he does, Wrathion wouldn't be opposed to tagging along -- he's nosy and he doesn't want it to be his problem but he wants to know what's going on. It wouldn't exactly be good cop bad cop, it'd probably be Slick being bad cop and Wrathion being the slightly-less-blunt but still pragmatic cop offering a mild hint of emotional manipulation now and then I suppose. He can, at least, do charisma and flowery words! Which are good if you want to twist the knife every so often on a bit of drama to sink the point in.