Locked at skaterized mission

I’ve been stuck on the main quest "Skaterized" since the beginning of the game because I’m missing the prerequisite quests.
The problem is that the quest "Stop Quick Drop and Roll" doesn’t show up on my map.
I’m not sure if I’ve already completed it and it didn’t register, or if it’s just not showing up at all.

I’m on Steam, my ID is: p0wny.sh_ctf