My advice to you is if you have a choice to fly out of Chicago on American Airlines,Delta or Spirit(which you should avoid like the plague) fly Delta if the flight takes the same time as American Airlines.Delta has this Cuba travel thing down very well and will answer all of your questions and sell you the Cuban tourist card for $50 either on the phone or at the check in counter on the day of your flight.I only advise against American because if an airline can't give you definitive answers about the operations of their own flights you should probably avoid flying with them.
Thanks - I find all of American airlines pretty awful tbh. Spent the last 3hrs comparing dates, airlines, bullshit fees and all that... Delta is indeed at least upfront about what's going on. The AA rep on the phone didn't seem to understand what a 'visa' even was, not mentioning having any info on it. I also tried getting info from the Cuban Consulate to see if it's any cheaper but after half hour of failed attempts to reach someone there I gave up... endless phone tag - typical.