Is there a certain criteria for being able to buy this in the cash shop? I know I've had a list of possible animals show up at least once, possibly when I hadn't yet trained them yet, but trying now (when all have been entered in at least some shows), it doesn't give me anything. I'm trying to buy extra shows because I accidentally entered an animal in several public shows, not privates...

You'll need to buy the extra 10 in the regular store first. ☺