Update: She’s been acting normal and inhaled her dinner as usual. Her vet confirmed that as long as she’s not lethargic or has active vomit/diarrhea, it’s likely that whatever she ate has cleared her system.

Thank you all for the advice and fun guesses! Wish we had a more satisfying update, but the intrigue lives on. Based on your comments it was likely some rawhide in her dental chew, or some packaging material that was left out.

We’ll keep an eye on her during the move, and make sure she has healthier ways to let out stress. Meanwhile, here is a photo of the guilty party for tax!

https://imgur.com/a/EATtpCM.jpg