If the Department of Defense payroll service does not use one the W-2 TurboTax partners you cannot import your W-2. Even if you were able to import the W-2 you would have to know the military EIN, the Control Number in box D of the W-2 and the Box 1 amount in the W-2.
Have you gone to the DFAS website and tried the ways to access information concerning your W-2 - https://www.dfas.mil/MilitaryMembers/
Have you tried the toll free number - Call 888-332-7411
