I thought the items added to the bundle were automatically available to people who bought the bundle, but that's not the case, I'll see if there's a solution for that.
I've added the "full bundle.zip" here: https://pixel-boy.itch.io/free-mix
I'm wondering if you have access to it since you purchased the bundle? If not, could you send me a private message on one of our social media so I can send you a key?