Thanks for the pic
You made me dizzy trying to work out the angle the photo was taken at
That does look substantial with reinforcing plates around the holes and likely the underside of the boot.
Now it's obvious it's not just a couple of holes drilled into the bootlid as i've seen on other cars.
If i go down such a mod, it will be some time away but i think i'd go the other boot lid aproach, one with a spoiler already attached...
Sadly it will make it much more costly than the $550 factory option
Bloody dealer games, i'll blame them
PS: curious why you have the spoiler off the car?