It still could be a veterinary issue, or at least have started that way and grown into a more universal training issue. Dogs can have odd responses to pain, and I have definitely seen some where their behavior is situational. In other words, she might listen at home because she feels safe, but pain combined with new surroundings on walks makes her unwilling to obey you. Depending on where you live, it is also possible that she actually is having trouble hearing you outside. If there's enough ambient noise where you walk (kids playing, cars passing, etc.) she may not be able to understand your commands, while in a quieter environment like your home, she can hear you. At her age, any significant change in behavior probably calls for a vet visit.
Otherwise, refusing to look at you does sound like an appeasement behavior. I would stay away from that dominance stuff, as it hasn't helped and may have made things worse if she didn't understand what you were doing. Instead, I'd recommend doing positive activities to help rebuild her trust in you and repair your relationship. Even 10-15 minutes a day of clicker training or other similar positive methods could really help, and surely you can spare that. Teach her that spending time with you and listening to you is a lot of fun! You can both reinforce her basic commands (sit, down, stay, etc.) as well as teaching fun tricks so she's learning something new. At first you'll probably want to lay a foundation by training this way in your house, but then move outside and see what happens. I've had a lot of success getting evasive dogs engaged and listening to me this way.
Anyway, that would be my suggestion...first a vet check to be safe, then if that comes back clear, fun training activities to rebuild your relationship. Like I said, it doesn't even require that much time, but you have to do it consistently--at least 4-5 times a week, and preferably every day.
edit: LOL I should know better than to leave the reply window open while I go make a cup of tea. I didn't mean to repeat the posts above, but I think it's great advice!