Do I need a unique PID for "MLA USB HID joystick" application?
In order for your device to be compliant with the USB specs, you must have your own VID/PID.
The form to request a Microchip development PID can be filled out on the sublicensing page if you continue to use the MLA VID/PID.
There is a risk of product failure if it is connected to another device with the same VID/PID. Conversely, the other device might fail.
For more information please read the VID/PID section in the 'FAQs' tab of the "USB MCUs and dsPIC® DSCs" page.