My dog was hit by a car and won’t eat and barely drinks

[Dixonn11]

Hi, my dog was hit by a car and went into shock. We rushed him to the vet where he was stabilized and we transferred to the critical care hospital. They did X-rays, blood tests, exam 3x and neurological exam by a speacialist. They said no internal bleeding and some slight bruising to the lungs and severely damaged brachial plexus. We brought him home and took him to a speciality clinic today where they did another exam, acupuncture and laser and perscribed new pain meds. My dog is extremely larthargic, won’t eat, even treats and little water. He can hobble a little if coaxed and can urinate although he hasn’t defecated in 5 days. I am worried that they are missing something and he will quickly spiral downhill. Any suggestions?