AA should check your papers in PHL. If they do, then the only check done in MIA probably is passport. We flew RIC-CLT-SXM on Tuesday, June 8. We could not check in online or at kiosk - had to talk with counter agent in RIC who checked for the negative test results and the (Pre-)approval from EHAS. The counter agent in RIC was very thorough and careful - after confirming everything, she entered fact that we were OK to travel to SXM in computer. In CLT, all they wanted was to see passport as you scanned your boarding pass - which I think they always do for an international flight.