Not a chance this is fake.
Just the scenes around the incident was edited or recreated. So was ,Probably, the "Right in the kisser" line, just before she got hit. Which I lol'd at.
I'm with Rex, can't see how it's real. The mass of a watermelon pretty high, it got a lot of speed on it there, that should at least be enough force to break any part of the face it hit, not to mention the brain damage from shearing. Ok some of the force is dissipated by melon explosion, but still the skin is pretty stiff and would impart plenty of damage to the face.
[ ] American corporations love taking these kind risks in a very litigious culture