Anything can happen. I will not be surprised. LATAM is the perfect fit to oneworld. But I think the south american business can be tricky. If LATAM decide to switch to star (I mean if). I will not be surprised to see IAG spending a fortune to bid on TAP.
Then again I would not be surprised to see TAM remain in star while LAN in oneworld just like Air China and Cathay Pacific.
Nothing is impossible.