The VI you attached had only 3 different cameras to acquire from - you may want to make sure that you are only trying to acquire from the correct 3.  
Also, you may want to make a separate camera file for each of the cameras since they are the same type.  This document explains how to do that:
http://digital.ni.com/public.nsf/websearch/F9235C5B145580AD86256C3A00716A26
You may also want to try acquiring from just 2 cameras at first and see if that works, then add on more after that.
Hope this helps-
Julie