I'm in much the same situation, leaving September 17 and having gotten no info from anyone I talked to on the phone at AA. The last I read on some forum or another (Lonely Planet's Thorn Tree forum has a lot of travelers that have been going to Cuba for decades and are pretty clued in about all the changes, and are staying on top of these issues with new flights) was from someone who was told by AA that they were getting some third party agency to handle the tourist card at Miami airport. No word about the "mandatory" insurance though. And no word on when this as yet un-named agency is supposed to be up and running in AA's Miami airport area.
Please post, anyone who has heard something more.