There is no question in my mind that it’s a crinoid. I grew up in a town in Southern Indiana that was essentially a giant crinoid bed in the Cambrian. I had so many pieces of crinoid. I even had a “flower,” which were really hard to find. Sadly, I lost it.

Here’s a bunch of “stems”:

Here’s a “flower”:

I put those words in quotes, because a crinoid is actually an animal, not a plant. Here’s a sea lily, one of its modern descendents.