Tethering/ long lead gives you some control. Go back to doing off lead ob with him contained in a room in your house with you. This will help restablish the notion o control without a physical link between you (the lead.) he has too many option right now for how he can avoid obeying you- you need to get that notion out of his head.
Then move into CC - while following a program for it. It sound like your previous experience has more to do with enforcing prior training than actual teaching and training new concepts. It can take a lot of repetition and proofing