Basically something has programmed him to think that pavement is dangerous and scary. You need to reverse that thinking.
Do NOT pick him up anymore and do NOT coo and feel bad for him when he freezes. In a dog’s mind this means he has a reason to be afraid. You’re actually encouraging his behavior and fear.
Build his confidence. Put him on the pavement and squat down a few feet away. If he comes to you pet him and say good boy. Give him a treat. Then move and repeat. He will learn that he is safe on the pavement. Don’t let him climb into your lap and hide. If he does this, stand up and set him back on the ground. Dogs pick up on their owner’s feelings, so be confident and he will be confident.
Also, try treat trails. One of you hold his leash and the other walk away and leave a treat trail to the yard you want to him to walk to. Then let him lead himself along the trail.
Let me know if these work. If not I will try to think of other ways to help. It’s hard to give a good plan without seeing the dog first hand, but at least this gives you a place to start. Have patience. Good luck.