As you said, once we meet they will be appropriately greeted regardless of who they are. [If that's not reassuring, he doesn't know what is. And yes, that's an unspoken "whoever brought you here is probably responsible for the shadows as well".
Actually, since Sebastian's now figured out The Solution for how to make these new weird powers go away, he removes his own cufflinks and tiepin, dropping them one by one for each new step and crushing them beneath his heel as he walks. Multitasking.]