If
If you look at the conveyor belt at MissAdventure Falls it's not very steep of a climb due to the fact guests are on there. Due to that the slide takes an enormous amount of space Universal just doesn't have.
Vulcano Bay has the most number of slides off any water park in Orlando to keep their guests entertained.
I'm sure they could add a borken AA if they wanted as seen on this great the TimTracker video.
Disco parrot.