AAA: call a constructor

public class MyService
{
   private IA a;
   private IB b;
   private IC c;
   private IDatabase db;

   public MyService()
   {
      a = ioc_container.Resolve<IA>();
      b = ioc_container.Resolve<IB>();
      c = ioc_container.Resolve<IC>();
      db = ioc_container.Resolve<IDatabase>();
   }

   public Result DoUsefulThing(string login, string data)
   {
      var ud = (UserData) db.Users_getUserData(login);
      if (ud.Uid != default(Guid))
      {
         if (InnerCheck(ud, data))
         {
            ///////////////////////////////
            // perform useful thing here //
            ///////////////////////////////
            return new Result(ResultCode.Ok, "");
         }
         return new Result(ResultCode.MethodFailed, "inner check failed");
      }
      return new Result(ResultCode.LoginFailedError, "user does not exist");
   }

   private bool InnerCheck(UserData ud, string data)
   {
      // for now it doesn't matter
      return new Random().Next(2) == 0;
   }
}

[Test]
public void TheClass_test()
{
   var r = new UserData(new Guid("9763A087-9971-4098-A21D-46DA3C71EC01"));
   
   // arrange
   var db = Isolate.Fake.Instance<MyDatabase>(Members.CallOriginal);
   Isolate.WhenCalled(() => db.Users_getUserData(login)).WillReturn(r);
   Isolate.Swap.NextInstance<MyDatabase>().With(db);

   // act
   // In order to call the constructor explicitely I have to create
   // the object here, all the fields are normally initialized, and
   // typemock magic makes db field behave as in arrange
   // "section" above
   var ms = new MyService();

   // arrange again :-)
   Isolate.NonPublic.WhenCalled(ms, "InnerCheck").WillReturn(false); // !!!
   
   // act again :-)
   var result = ms.DoUsefulThing(login, "useful-data");

   // assert
   Assert.AreEqual(result, new Result(ResultCode.MethodFailed, "inner check failed"));
}

TypeMock.TypeMockException: 
*** No method with name .ctor>b__0 in type MyService exists.