@Brian > If you have the decks correctly linked, then yes, you should be able to browse the tracks from a linked USB drive. Be sure that each player has a unique ID number and that the cable is seated properly.
If you have player 1 in HID control mode and you're trying to link player 2 to player 1's USB, that won't work, but besides, you can pull the USB stick out of player 1 and pop it into player 2 anyhow.