Hello, I would think so. If you can wait, I have the VIM version with the GPIO header mounted. Tonight, I will connect thru GPIO USB and let you know what I find.
Update: Yes, connecting TB thru the GPIO pads will work with the configuration you have indicated in your post. While I had no B type connector, used type A cable, I assume as long as the wires are connected correctly, B should also work.
If you solder a USB cable directly to the GPIO pads, it would be a good idea to not allow those leads to be pulled on. Some type of mechanical strain-relief should be used.