My best suggestion to overcame it, is to create your own analyses to retrieve the required info. The first step would be to find the correct solaris command. I have done a quick search and found the command “zlogin zone01 mpstat 2 2” that seems to produce the information that you need.
Once yoi have identified the best command, you can create a BES action that runs the command and redirects the output in a file. Then you can use the “file” inspector to grep it. The following is an example of the “lines of file” inspector that i got from one of my Solaris test system having all 16 CPU shared among zones. I guess you get only one line if you have one CPU capped to a zone. Hope it helps.