I am not sure if that would help. I have seen some of the senior mgrs in my previous company, who were doing 3 years part time MBA from NMIMS. They had to attend classes on weekends. But part time MBA cannot be equal to a full Time MBA. I had asked this question to a counselor who had come to my college. He said its not worth it.
But I feel that an Executive MBA would be the best option for him from the top institutes. It gets completed in 1 year, but it costs a bomb and If his company sponsors it, then it would be best.