It's visibly very clearly a fossilized sea shell. You are being a useless pedant about the author's choice of verbiage.
Remember, the same author says "I found a seashell in the middle of the desert!" "shouldn't be here" and "coastline 500 miles"
And that analysis finds out that the shell the assumed fossil most resembles is completely out of period.
And I think you’re arguing yourself into a hole here.
What makes you think I know nothing about the topic? I have donated - at their request - three fossils to national museums.
But I’m not an expert by any stretch.