Without more info it's hard to know what's actually going on. What's an AOT?
Has his back & saddle been well checked to ensure he's comfortable? Has the horse(and the people) been well trained? Does he understand how to respond to their cues?
Has the horse had his mouth examined, teeth floated, to make sure there's no pain? How was the horse approached & asked to accept the bit? What did the people do when he evaded them? Some horses, innately or because of previous experience, just can't stand a bit. Has he been tried bitless?
I would start on the ground with this horse, teach & strengthen the behaviours you want, like yielding to pressure. Use lots of 'approach & retreat' and positive reinforcement(reward) to get him comfortable with everything. When I first got on his back, I would check that he was responsive at a stand still before asking him to walk. I would ensure he was responsive in a walk before trotting, etc. I would also ride in a safe, enclosed area to begin with, so I could *ask* politely for something, then persist gently until he responded, rather than having to try to force him to do things because of safety concerns.