Did my Betta kill my Ghost Shrimp or did it have a bad molt and get chewed on?

I saw it and thought it was the discarded skin.. On further inspection it looks like a dead shrimpy, with it's tail missing, as well as some of its feelers. :( They're like 5 bucks each at Total Pet! AAAAWWW MY SHRIMPY! What happened? Should I get another, bigger one, or just get another guppy or something? I'm sad.. help? advice? The pet store said I shouldn't need to get Iodine to help them molt well, as their shrimpies always do well. Now that I discovered them I love em, they're so cool and interesting. I know I need to add more hidey places for em, and I'll be doing dat with the upcoming gst refund. I think Bluegrass the Betta is nibbling on the dead one :'( HALP?