I like "Clouds of Why". It's an intriguing title that also works well as a theme and closing.
The loose pace and structure of your lines fit the subject. They strengthen the whole impression of dealing with things that are visible, definitely there, but still vague and impossible to tackle.
I feel that "fiction--diverted into facts" in not only has a nice ring to it, it's also accurate. When we turn something over to the part of our minds that projects "what next?", "what else?", that part does not distinguish that it is only conjecture.
On the other hand, "Resigns me" sets my internal grammarian to jangling. Resign basically means leave. If "This riddle of fiction" has resigned you, it means the riddle has departed, and no longer inhabits your thoughts. What you've written says the opposite. I see how pairing Resigns with consigned helps close the last two lines. For me, though, it doesn't overcome the objection from my irritated grammarian. Have you considered switching the order: Consigns, then resigned? Or you might want to try substituting binds, assigns, confines, or something similar. These changes might require some adjustments to the last two lines, but I don't believe it would be major surgery.
As I said, I like "Clouds of Why". I hope my suggestions provide you an idea for making it a bit better.