They will be fine and wade through the snow. We get a lot of snow in the Black Hills and they do fine. We got a couple feet of snow over Christmas and they came walking through it into my yard just like every other day.
I honestly know nothing about deep snow and turkeys, as we normally do not get that much snow. But I would have to think any bird that pitches down into 2 feet of soft snow, is doomed? Sure they will stay on roost for a good while, but eventually have to come down.