For what its worth, Westcom dispatches everyone on LAW 1. Just like Polk County dispatch. (except they split some agencies off to LAW 2)
You really wont hear anything on those Waukee channels except for the occasional chatter between units.
The way Westcom has their system set up is causing a lot of confusion on the forums it seems. Each agency has a LAW 1, 2, 3 etc as well as Fire 1, 2, 3 and some other channels. Westcom as an entity also has some 'master' groups that their dispatch consoles reside on. The dispatcher will patch the master LAW 1, 2, 3 groups to the other agencies LAW 1, 2, 3 respectively. Because of this, the group that appears on the scanner display essentially relies on the order they patched them together. I don't know if it's the first selected or last or random. Whichever the case is, it can change any time they redo the patches like when they split an agency off for an incident. Because of this, your scanner may display a group ID that says Clive Law 2 or Urbandale Law 1, but its actually a patch of all of them together. This is a throwback to patching the new and old systems together, they patched them together exactly the same way. The only groups that are actually by themselves are the chat channels like law 4, fire 4, public works etc. But keep in mind, they can patch and and all groups together whenever they want. The only way to know would be to use a utility like Unitrunker to see the patching process and see what flags are set when the call request is made.
Hope some of that helps!