I ordered my ROG 3 from Flipkart in India and it got delivered yesterday. I noticed that Asus has changed the design of the case that is provided in the box. This new design also covers the vent completely. Attaching pictures
The case you are showing doesn't look genuine. I have purchased my rog phone 3 and the case that came with it is completely different. Mine doesn't cover the vent.
Yup! @p.o.dupuis is correct. This is definitely not the one we get in the box. You should contact your seller and investigate.
Don't worry, they've just updated the case design and the same has been done for the neon aero case too.