All I'm asking is how many hours he worked so far, and why it isn't finished after 3 weeks. Also, why is there no speed estimate?
You must not be a developer.
Translating code from one platform to another is an all-or-nothing project. It either works, or it doesn't. There's no "we're half way there, lets run some benchmarks".
There's also no magical progress bar that tells you how far along you are. You could think you're 90% done but have no idea that you'll spend the next 3 days debugging a single function.
You can't know how long it'll take. You really, simply, cannot know.