Yes, it seems to work. Used your index.html file with estonian voices (added .wav extension), edited your index.html and changed "en-GB": "english" with "en-GB": "estonian". Well, at least it says the first "command" as I'm inside and the first turn is only 10 meters away .
I'm trying to use it tomorrow in real situation

Keep up your good work

It's good to have voice guided navigation but for me the offline search seems even more important...