There should be no difference between what you see in CC and iClone, given the same environment and other settings as the native renderers are the same.
A way to verify this is by opening an CC project in iClone, which you can do by copying the CC project file and then changing the extension form ccProj to iProj.
Make sure that in iClone the Max Texture size in Preference (Ctrl+P) is set the a high value such as 4096x4096. A render from CC or iClone should be the same.
I can't help you with Unreal, as I don't use it.