Do you think you could tell me what specifically looks wrong with mine?
As far as I can tell - nothing. There are many ways to skin that cat, and titration with iodate solution is one of them.
That being said, I am not entirely sure it is the best method. I was always under impression reaction between iodide and iodate is slightly too slow, which is why it is better to use it to prepare iodine solution first, then to add reducing agent and finally titrate excess iodine with thiosulfate.
Or at least, all classical analytical chemistry books I learned from had always suggested this approach, and I always assumed they knew better.