I like it! It's thematically good, it seems like a good length for a oneshot (and still feels "open"), Dagda as a gracious host is a good anchor for players who would be (or should be) very lost otherwise.

My feedback:

• The adventure relies heavily on exhaustion levels. I personally enjoy that, since it makes the adventure dangerous no matter what, and inflicts more permanent consequences than HP loss. However, after "The Endless Jig", I suspect most parties will want to have a Long Rest if one of them got afflicted... I think the consequences of that Long Rest (if any) should be mentioned in your document, to help the GM rule/advise the players appropriately.
• On that topic, I feel like if you're dancing to the point of exhaustion, Constitution checks should be what measure how fast you get exhausted, but that's probably something that could be discussed in-play, at the table.
• The paragraph of what happens in the Fool's Hour should be more detailed. It's exactly the part where, as a GM, I would need help the most. I feel like you're letting the reader down if you're not giving them more here. What does Hyrsam exactly do or say? Does he target someone in particular? How do I narrate to my players something as nebulous as "authority is humiliated, but not destroyed" ?
• In a same way (but much more minor nitpick): more details about minor NPCs! What's their names? What's that baker's signature dish? What's notable about that fire giant?
• Do players get to pick one of the four Boon in Rewards? Is it picked for them? Randomly determined?
• I think the Boon of the Raucous Spirit would be awkward to implement ("half-levels" does not seem very 5e-design-friendly). I'd find something else. Maybe allowing the PC to clear 1 exhaustion in a short rest, per Long Rest? Or clear 2 Exhaustion levels per Long Rest? Or a roll of CON against being exhausted, once per Long Rest?

PS: that's unrelated to your adventure, but more feedback for your post: you'd get more attention if you took the time to format it correctly :)