iCal Shared Not Appearing on iOS Devices But Do In Macs' iCals

I am running Mountain Lion, but this issue was also happening in Lion. As a former Apple Specialist who specialized in iCloud, I've stumped myself and several AppleCare reps. They have forwarded this on to the engineers.

I have three calendars that I share from iCal to my family's iOS devices and Macs. The calendars are updating fine on all Macs, but are not updating on any iOS devices. They used to update slower, but it's gone to nothing.

I've tried everything under the sun including:

1. Turning iCloud on and off on each device AND on my Mac.

2. Restoring the iPhones as new phones

3. Exporting the calendar, importing it as a new calender and sharing it. Still doesn't update after the initial setup.

4. Quitting the Calendar on the iOS device and reopening it and restarting the iPhone.

Is anyone else experiencing this problem? I've totally stumped Apple. And remember Steve said, "It just works." It's not.