Hi similar issue has occurred for me, the download's page just doesn't have the "Get you key" button on it. Either way hope you have a pleasant one and this can be cleared up soon :)
According to itch, there are plenty of Steam keys remaining. I am not sure why the button is not appearing >:(
I might have to contact itch. It's possible I forgot to give the bundle permission to distribute keys? You'd think I know how this stuff works, but incidentally I was born in a cave and live on moss in my corner. That's where I met Katja. I'm sorry that I just said that. It's very late.