Falcon 5W input options?

I have a Falcon 5W but am having difficulty understanding the input for the device. I have a USB-3 thumb drive but cannot make it read it. It seems that it only takes input from the microSD slot.

I do not have a computer to attach via the USB-3. Am I reading this all incorrectly or do I need to do something to make it read through the USB-3?

Also, it seems that it will not read a 64GB microSd card. Is there a limit?