be prepared to get a grow out tank though, its always hard when you have a big cichlid in a tank cause trying to add to it you need the new fish to be of similar size.
I've heard of african cichlids working with crayfish and all cichlids do differ in personality. I had 2 yellow eared sliders that lived with a convict/sajica hybrid for years. sometimes things that shouldn't work, work just fine.
IF you was to get it working, you would have to have the cichlids introduced to the crustaceans at a young age, and if they grow up with them, they will not view them as a threat.