Yes all three are on the same fuse. See below diagrams. Take them with a grain of salt, these diagrams are from 2017 and VAG likes to change things all the time, especially which fuse does what.
Screenshot 1: Fuse 40 definition states sockets U1, U5, U9. and U18.
Screenshot 2: You can see the fuse "SC40" connects at "B150" to three points on another diagram, points 436, 443 and 447. The numbers in the boxes refer to the numbers at the bottom of the page; you find the page with the numbers and that's where the lines reappear.
Screenshot 3: The three red/green lines reappear, going to U1, U5 and U18. U18 is the one in the luggage compartment.
Screenshot 3 also doesn't explain that:
U and U1 are the same thing, but it depends on the smokers pack. If smokers pack installed, then you get a lighter socket with the heated element. Otherwise it's just a power socket.
U5 and U9, same as U and U1 above.
U18 - no option to light a ciggy, just a power socket.
If you have the U13 230V socket in the middle row seats, then that's a different fuse and the other pages of the diagram imply that both the 12V and 230V outlet there are on fuse 46 but the front and luggage ones remain on fuse 40.
Here is the fuse box. See fuse 40 (highlighted yellow) has room to move down (red marking) which is different to all the other fuses around it. To repeat, not all cars had the metal contacts fitted in the lower position. Mine did not. You can check yours with a flashlight.