New puzzler: Missing piece etiquette on buy/sell/trade groups?

Hi puzzlers!

I completed my first 1,000-piece puzzle a few months ago and have since done 3 more (I'm hooked!!!)

After reading a bunch of rave reviews, I got my first Magic Puzzle Company puzzle on FB Marketplace. It was such a fun build, and I loved the easter eggs in the artwork. I offered it up for trade in my local puzzle B/S/T group and received another puzzle from the same company. But when I completed it, I noticed it was missing 1 piece. The trader was super nice when I asked her about it, and even offered to trade my puzzle back. But I really think I lost it in my home: I have a dog AND a toddler so I can't imagine I'll be seeing it ever again.

Is the puzzle a dud now? I don't have the time to make a replacement piece, and I'm keen on getting this off my hands for another puzzle from MPC. Are puzzles with missing pieces unlikely to be traded? WWYD?