There was a whole series of other opposition groups that fought in the revolution and a whole clerical faction that backed other groups and opposed Khomeini, like Mahmoud Taleghani who mysteriously died in 1979. While Khomeini centralized the opposition, it wasn't without violence. A lot of people seem to have believed he was little more than a figure head for the revolution and would step aside when the shah was gone and that the Bazargan government would pick up where Mosaddegh had left off. Before Bazargan even stepped down the Revolutionary Committees were disappearing critics and the Hezbollahi were beating journalists.