I believe that EZE is in the path - barely. Good luck. Most things probably booked up last year. I had considered adjusting my schedule to be able to travel there during the eclipse, and decided that between the weather and the hassles (and having just seen the perfect eclipse in Salem, OR), that I'd pass.
I'd consider taking a close look at the totality map, and staying at the Holiday Inn Ezeiza for a night, if rooms are available. It is probably in the totality path. I'd expect traffic will be a quilombo.