Good thing you waited.^^ Although your reasoning sounded pretty well thought out.
I was thinking the croquet set would be used more in destroying the cookies. I'm leaning on the cookies being eaten with a tiny fork.
Now like you said Junior is hyper and that could be from eating the cookies. If the cookies were eaten (with the fork) wouldn't Junior make more sense as the primary suspect than Carlo? Carlo would be motivated to sell the cookies. The only thing he could use to transport the cookies would be the takeout container and that has been ruled out.