Strange has literally all of the reflections to look through. As such, he doesn't spot Reira trying to signal him immediately: it's a little bit before he shows up in the reflection of the metallic dish...and then just instantly goes a bit pale when he spots Ignatius trussed up like that.

He failed him. That's all Strange can think about right now, that he failed Ignatius. And, no matter where the other are, there's no way they can get back to the party in time enough to save everybody.

"Be careful of those chains," Strange murmurs to Reira, still looking a bit sick. He's at an awkward angle where he can't see everything, but he can see it well enough. "They're probably iron."