I think you need to cut AS a little slack here. It is only going to officially know what its partner tells it. And with after 15 years' experience with this airline (group), I am reasonably sure that its partner hasn't yet told it much.

I flew out of SCL last Sunday (not on LA) and you'd not have a clue that LATAM was any sort of airline, unless perhaps picking up a LATAM Pass application. One of the non-LA airline lounges had the old Lan Chile logo (a great one) on the departure monitor next to the LA flights.

Note that I don't defend AS on its lack of LA knowledge by several agents. Over the years, I've had to educate quite a few of them, such as one who told me I couldn't fly Lan Chile to Chile.