Bishop Braxton might be right that there is insufficient 'inclusion' of Catholic. On the other hand, it might just be to the advantage of, at least, the clergy. It doesn't take much googeling to find that Catholics were a bit late to - and a bit mixed about - the process. A tardiness not totally obscure to Dr. King as well. 
A little story: In the summer of 1964 several Jesuit "Scholastics" in clerics and a woman religious, in habit were among the packed-congregation at the Riverside Church on Columbia U. campus for his rendition of the "Knock at Midnight" sermon. After the service they joined the long line of well-wishers who met with Dr. King, his wife and children. Scanning the five person line of solid black, he greeted each of them warmly as he shook their hands.  While specific words are long forgotten, his genuine pleasure at their presence was tinged with a gentle tease.