If I found the right order, this quadstick was order configured for the Nintendo Switch:
At power up the default configuration will be for a Nintendo Switch console, not a PC.
Look in the box for a copy of the list of configuration files that were loaded into it. You will find this list:

You will need to select the #5 configuration file to gain access to the flash drive for QMP to be able to make changes.
Once it is running the Mouse2 configuration, you will be to use QMP with it.