There's some good ideas here, and I think with some tweaks and polish it could be pretty solid game.
The first boss is quite hard (as many have pointed out), and while it was frustrating and I do think difficulty tweaks are necessary, it felt doable and I found it to be engaging. Rolling fatigue or boss buff honestly didn't change the fight much in my opinion, but rolling double down felt like an auto loss. Fighting two of the same simple boss at once is generally a good way to make a fight more interesting, and would work here if the difficulty is toned down. And while it's very on theme, I'm not a fan of a boss' difficulty being determined by which random buff it gets. I'd say if you want to keep the spinning mechanic make the different ones more comparable difficulty wise but unique in how they affect the way you have to approach the fight.
The second boss was less difficult but still pretty challenging, and it's a unique concept for a fight that I haven't seen done before, but the time spent just waiting for the coin to fall made it less engaging for me personally. Also idk if it's intentional or a bug but the damage zone on the bottom does two hits of damage which I felt was overly punishing, though the coyote time did help remedy that and was a nice touch.
The third boss is where I gave up, I just couldn't envision myself beating it. The double cherry attack felt particularly unfair, especially when paired with other attacks.
Anyways I've yapped enough, the game has potential, and there's lots of little details I like, such as the cards as health and the little cane spin you do when you stop moving. Good job :)