The fact that you didn't see any subsequent scans means that the bag likely didn't have a scannable backup tag (the rectangles that usually get stuck directly to the luggage)

Were you a good traveler -- i.e. did you have at least one tag with your full name on it on the outside of your bag? If so someone I nthe bag room could have very easily looked up your itinerary and sent it on its way (though it is curious that it didn't get a replacement ABT, MBT, or Rush tag, especially going internationally.

If it was loaded on EZE and arrived the ground handlers likely sent it to the belt by default -- if no one has grabbed it they'd wait for a claim.

Incidentally this (and the fact that I have multiple PTouch label makers in not afraid to use ) is the reason every side of every bag that I check has a "(my full name) * (internationally dialable phone number that also matches my MP profile) * (email address)" sticker on it -- not so large that it can be read from a distance but large enough that if you have the bag in front of you you can't miss it.