I assume you're "SoCal Edge" on the SMR forums. Here's a photo to show that USB2 does in fact work (if my attachment works). As you can see, it is playing one of my favorite podcasts via USB2. I added this to my Flex today. I previously had the same cable on my last vehicle, which got left at the dealer last week when I picked up my Flex.
EDIT: The Sync module (APIM) on every vehicle has a spot for a second USB port. Once you plug something in, it will work. You just have to find the Sync module and the right USB cable/adapters. I used an extra cable and got a $4 adapter. Voila, 2nd port. Very low effort with a high return.