This could just be in the season, being that we are in the Ramadan fast period, and since everyone has got a muslim friend or two, rapper TI might just be adding an “Alahamdullah “hashtag because he has a Muslim friend. Forget the seemingly segregated world uptop, many people now enable or support their friends and their religious believes. For example, some christians don’t fast with the Muslims, but they move some meal times to suit that of their Muslim friends after they must have broken their fast. Some don’t engage in anything sexual with their partners because their Muslim friend is going through the same thing.
So this might not be him being a Muslim, but a friend of a Muslim.