I would not go to IG to reach Mexico.
They have moved the Epcot drop off point (again) for the main entrance. It is right near the monorail station
We used it in December and found it very easy. We also always use it to leave Epcot and go to the airport. Which we also did in December. Again, it was very easy and did not take long at all. We were staying at BWI earlier in that same trip and pick up there was no faster.