Pink eye is a virus so sitting in the back of a convertible won't give it to you. Coming in contact with a person who has it will give it to you. You may have gotten dust or a bug in the eye in a convertible that caused an infection.
To repair a Volkswagen convertible top that is coming apart at the seam may require re-stitching the seam and then placing a canvas patch over the entire seam to prevent further damage to the top. This should be done on the inside of the top so that the car's appearance is not altered.