I haven't come across the iCP2 before. However, it says it behaves as a HID device, so there should be no problem mapping it into the Amiga keyboard/mouse controller.
The VNC2 chip contains the translation table. So yes, it would behave just like an original amiga mouse / keyboard as far as the system is required.
The design also convert inputs back into PS2 standard and sends these to the ARM, so you can control the OSD as well.
/Mike