I think that Paul was writing to the Roman congregation, not the body of elders which shows it is a personal decision. Plus I think it is a personal decision in the way that witnesses are told to consider their forms of entertainment. After all the first century congregation we told that the only laws that applied to them was eating blood, fornication and eating things sacrificed to idols.
Plus even if disfellowshipping is scriptural, judicial committees certainly have no basis in scripture.