If the vet advised to keep your horse in keep the horse in. I had a horse go to surgery and was told to keep in. I kept the horse in with small hand walks when appropriate as advised by the equine surgeon. We went away on vacation and had a friend take care of the mare. I told them hand walks and stall rest. I don't know what they did but when I came home the pasture was torn up and the mare had a broken leg. Long story short we put the mare down and I never learned what happened to the horse while I was away. Some horses don't listen to pain but push through it and seriously injure themselves. It was really upsetting because she was the sweetest horse. Still, if you and your friends think you know better then your vets 8 years of education, 3,000,000.00 dollars of debt and years of on the ground experience then go for it. Just don't be ticked off when your stuck calling a back hoe and paying for that final injection.
Is there another horse that the pacing horse could go out with? If he does not hurt himself, the fence or other horses the let him figure out that pacing does not get him want he wants.