Hey @jgutel,
If you do not need the X9 connector as a HOST mode interface. Then I would think it would be fine to leave the design with the J2 pin in the open position (or not included), and design it as shown in the schematics.
It would still make sense to tie the ID pin to 3.3V (with resistor, as schematics show) This is an input pin and what signifies OTG or Host mode.
For a bit more information: USB_OTG1_ID is the ball name for the USBO1_ID, these are the same pin with different naming (you will see them concatenated together sometimes).
-Eric