This has nothing to do with doneness. The meat may contain nitrites. Some can come from nitrates or nitrites in the food and water supply of the bird itself. Nitrates occurring in water may also be introduced to the bird during processing. While nitrates are not pink, they change into nitrites, that do lend a pink color.
Smoked turkey does look pink.
These are just several reasons that poultry may not change color the way you expect it to during cooking. We often hear how important it is to use a thermometer to make sure meat is done. But consider how a thermometer can also help you be sure your poultry is not overdone. A reliable thermometer is the answer to both food safety and food quality.