Unattended Uninstall Script - command line equiv to Add/Remove button or better approach?

Hey guys
Got a problem. I need to create a script that automatically uninstalls ICS Viewer 6.0. I need help on how to tackle this.
After some research, turns out PureEdge does not support quiet uninstall string via MSIEXEC (which is what I normally use - thru ConfigureSoft). So I though, ok I'll just create an exe using Winbatch and just kick off the uninstall and have it automatically click the "yes/no" buttons to allow it to uninstall by itself. But my problem is, how to kick off the uninstall command?

I tried..
1)  RunDll32 C:\Program Files\Common Files\InstallShield\Engine\6\Intel 32\Ctor.dll,LaunchSetup "C:\Program Files\InstallShield Installation Information\{E0000600-0600-0600-0600-000000000600}\setup.exe" -l0x9  -uninst
which (according to ConfigureSoft) is the uninstall string, but I tried it via command line and nothing happened.

2)  msiexec /x{E0000600-0600-0600-0600-000000000600}  (which is the uninstall key for ICS Viewer)
First a "Windows Installer" window popped up asking to continue. After the "yes" click, an error pops up saying that it's only valid for products that are currently installed, which doesnt make sense since the key is correct and it IS installed?!?!

What confuses me though is when I pull up Add/Remove Programs and scroll to ICS Viewer and click "Add/Remove" that way, it seems to uninstall fine. So my question is, is there a way to access this button via command line so I can kick off the uninstall? Is there a command line equivalent to this?

I know that appwiz.cpl is the command to run the Add/Remove Programs, but what is the command that actually runs when you click that Add/Remove button??! Is there a way to include parameters with it?

Or is there a better way to do this that I'm completely missing? Shouldn't msiexe /x work??!

Any help is appreciated, thanks!