Do you have more than one C.exilicauda? Are you keeping them together?
Your collection seems to mirror mine. I (well, Tamara) have a H.troglodyte, an Opisphathalmus sp., and C.exilicauda. I also have P.transvaalicus and A.bicolor, but you have to substitute H.spinifer in for your P.imperator. What else do you have?
In my experience, C.exilicauda are not that agreessive towards each other and really aren't even that agressive towards people. They are more runners than fighters. That being said, venom potency is considered to be quite severe, though not life-threatening for adults.
Well I had two Centruroides exilicauda together for about a year but one of them just died two weeks ago. I am working on a 30 gallon hexagon Centruroides exilicauda encloser right now. I hope to have it done by mid june and will house a colony of fifteen in it. The only other scorpion have at the moment is a Heterometrus longimanus, but I do hope to get some Hadrurus arizonensis, Hadrurus spadix, Scorpio maurus, and maybe some Centruroides vittatus by the end of may.