What Could Foul Smells In Mouth Post Gastric Vasectomy Suggest?

Dear doctor,My cousin underwent gastric vagotomy 2years back at CMC. In detail he had ulcer in his duedonum,when they tried curing that his duodenum shrinkined and he struggled eat food, so they had routed the food flow in another part o oesophagus. His recent barium swallow test resulted in positive. He is yet to undergo endoscopy from cmc. but the problem he is facing is if he eats rice from restaurant, full digestion doesn t occurs and smell comes out of his mouth,rarely he vomits but he has food in large quantity but leads to smell in his mouth which is bad. We heard about billroth hospital,thought of consulting you before we could come. Please provide the solution..