You are a good person.
Cut it up, take a photo of the pile of cut up plastic with no number sequences showing.
Notify no one, dispose of it safely, retain the image, but respond quickly to anyone who may inquire, but that is very dicey. You should neither confirm, nor deny any information, scammers are very slick, and will resort to anything to get you to even say your last name or email - and you should disclose NONE of it. Make them email you, airbnb, and have a written trail of every word.
Simply, I admire and respect you - but spend no more time on something a likely matching identity person would have shut off the card with a flick or the wrist likely before you made the bed. and you would have received a fast panic contact long ago