Since the Turkey has been frozen during those 2 years that means that the bacteria wasn't able to affect the turkey or grow on the turkey.
So a frozen turkey that has been kept frozen for 2 years is perfectly safe to eat but it might not taste as fresh.
I've even kept a turkey frozen for nearly 3 years before that I forgot about at the bottom of my deep freezer in the basement and it was still fine to eat and I cooked it and put it in with some stew and it made a good turkey stew.