Any veterinarians out there good at figuring out unique cat cases?

Other possibilities: esophageal tear or ulceration, gastric ulceration tumor or stomach worms, something stuck in the nasopharynx, nausea, string foreign body. I would recommend general anesthesia with an upper GI endoscopy with examination of the nasopharynx, sinus X rays, biopsy of the stomach and upper duodenum, prophylactic deworming and antibiotic treatment for Physaloptera and Helicobacter, and cerenia for nausea plus famotidine as a H-2 blocker. if those don't help, referral to a specialist would be in order.