I am afraid that I'm a little confused about your description. Which shield do you have? I've just searched on the Shield Testing Report document and I found an Adafruit Servo Shield and also I found another Servo Shield from Renbotics, so both shields are supported for the Galileo Board, but I don't know if you are referring to a different shield.
We are following up on your post Adafruit Servo Shield and we would like to know if you still need help or if you already have an answer or solution to your question. Remember if someone replied to you with a helpful response you can mark it as correct or helpful answered. We will be waiting your response. Have a great day.