If your incoming flight is on time and you already have your GRu BP no problem at all. At worst you may need to plead shortness of time when passing through security again, but probably not even that. Since your going to GRU at 9:35 PM from E that'll be AA. You'll have plenty of time if you don't dawdle.

Avianca is in the new Terminal J, you're leaving from the old terminal E. Because of construction teh exact entry could change. Just ask your TSA contact, they'll advise you the best route to take.

My recommendation is to go outside the terminal J after your interview, staying at departure level, turn left and walk quickly, you'll arrive at E in about 3-4 minutes maximum. You can do the same thing inside with air conditioning, but it will be fairly crowded. Nobody will be outside, so you'll save time, if you're short of it. You'll know you're there when you see AA curbside bag check desks.

Security delays then for the AA gates are from 1-7 minutes according to the TSA. I frequently leave on those flights and rarely take more than 5 minutes in security.

So, don't worry. Ignore the horror stories about MIA. As long as you walk quickly you'll make it.