You have a rack, right? If you do, is there any way you can rig up a system to lock the tubs so they can't be shut? Even a length of pipe and a padlock and some holders for the pipe would do it. If the back's closed off you wouldn't need to do it for the back. It'll stop anything like this happening again even if she never sets foot in that room again.

She's not sorry about what she did, she's just sorry she got caught. I wouldn't have forgiven her for stealing one of my snakes and selling it off. I'd have shut her out of my life just like that.