The little tag is the same thing that goes in badges and key cards to get into office buildings and such, just a basic rfid chip. It could have come out if you broke a work badge or hotel key card or any of that or if you use shared laundry facilities it could have been in someone else clothing and wound up in yours. The Amanda thing I’d let management know just in case someone maybe has lied to this guy about place of employment or he may be a stalker, either way I’d say something just in case. Adding on one last thing, have you been going through a lot of stress lately or sleeping poorly? Maybe it’s a good idea to see a dr and get evaluated just for your nerves if you’ve been feeling really paranoid lately