Castiel has never heard of two captives actually arriving together in such a way, and so he doubts that Hiccup fell off. He may still be here, but he wouldn't say that Toothless should count on it.

It's not often that there's someone (or something) that takes a statement more literally than Castiel himself does, so the remark about feathers throws him off for a moment. After a pause, he responds.

There is magic involved, yes. An immense amount of it, if it can keep all of us here.

As much as he might wish he could offer more detail than that, there's still so much they don't know about Wonderland and how it works.